Then again type c could be good for a emergency defibrillator lol
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Ok, I think I will approach this from a slightly different and hopefully more useful and less confusing direction.
That part I highlighted above ābecause the amperage is fixed across the entire systemā is the wrong reason to choose one type over the other. BOTH types do that very well already and one type does NOT do it better than the other. The labeling on the drivers is misleading and confusing and that has resulted in the CV version getting a bad rap for a completely fictitious reason. That is all due to a misunderstanding about how CCCV supplies work.
In any case, the main thing to know is that one type is optimized for hi voltage/low current and the other is optimised for hi current/low voltage. BOTH will work equally well - as long as your LED string falls within the Constant Current range and voltage range for that particular driver.
Look at the spec sheets for the drivers. You will see the following:
Pay particular attention to the voltage numbers under line " Constant Current Region" as well as the numbers under āVoltage adjustment rangeā and āCurrent adjustment rangeā.
Those are the numbers you need to use to select a driver.
Here are the steps I go through in selecting a driver.
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Decide on the max total power for your fixture. That dictates the number of Solstrips you need to have. So if you want a max of 1000 watts, and you dont want to exceed the Sol Strips max rating at 48 watts max = 21 solstrips minimum. That max power will also dictate if one driver will work or if you need more than one to meet the demand. If you need or want more than one driver, then you need to go through the steps for various combinations of series/parallel setups to see what works best for you. Neither one is necessarily better than the other. For BOTH you need to stay within the ranges dictated in the spec sheets. You want the max power for your LEDs to fall just under or at the max power for the total number of drivers.
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The next question is series or parallel. If you are not worried about hi voltages, then you are free to use the H series or the C series. Either one will work equally well if the circuit is designed correctly and wires are sized correctly.
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Now, you need to look at the āConstant Current Regionā voltages. If you have say 10 strips in series, that adds up to 240 volts. That 240 volts MUST fall within the min-max voltage listed in that row. If not, the driver will not operate properly and may not work at all. Ideally, your solstrips, or what ever brand, in series should add up to close to, but NOT over the max voltage listed in that range. That will help run the driver at max power for max efficiency. You can go a tiny bit over voltage as the drivers have some excess to play with, but not much at all. Best to stay under.
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Next, you need to look at max current rating for the driver. You want that to also be just above the max rating for all the LED;s together. In the case of solstrips, 2100ma per board. So, you need to add up the amp draw for all the boards - looking ONLY at the parallel parts of the circuit - to determine your max amp draw at max power out.
So if you have 3 strips in series and have 4 of those sets in parallel (total of 12 solstrips), that would be 3S4P (3 series x 4 parallel) your max voltage would be 3 x 24 volts = 72 volts and the max current would be 4 times 2.1 amps = 8.4 amps. You would choose a driver that had those numbers for max voltage and max current WITHIN THE CONSTANT CURRENT RANGE listed in the specs.
Note that you can go all series (12S1P in this example) or all parallel (1S12P) or some combination (like 3S4P or 4S3P or 2S6P) - as long as the total voltage AND total current numbers fall within the spec sheet CONSTANT CURRENT REGION ranges.
For a total of 1000 watts, your going to need more than a single driver, so you need to play with the numbers for the H and C series drivers to see what combination fits your requirements and what is the best bang for the buck or what fits your comfort zone best.
Neither method is ābetterā - in any way at all - than the other - as long as proper circuit design is followed. For either one, you need to properly size the wiring and follow proper wiring techniques.
Hope that helps 
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If you look at the spec sheets, the external āpotā or PWM drivers, regulate current only. That is a little comlicated because in order to change the current, the voltage has to change. The current draw is dictated by the voltage the LED 'sees" across is connection points. In short, you only control current directly, voltage is secondary.
With the internal pots, you can set both limits, but again, the series number of LEDās and the current limit take precedence over any voltage settings.
Also, its important for BOTH total voltage and total current to fall within the āConstant Currentā region. So keep the totals with the ranges listed in the spec sheet.
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Another point to consider.
Remember that your light fixture is going to be inside a chamber that potentially has hi humidity, wet surfaces, and possibly sprays or drops of water, and nutes floating around. In that kind of environment, with a hi voltage setup, voltage leaks/shorts from the PCBās to heat sinks or the metal frame, or along cords, wires, support cables, hangers, etc, are a real possibility. Thats the main reason I went with a parallel setup - to keep the voltage down to a safe level inside a risky environment.
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After all of your advice, I think Iām going to go with the 320h-24a/b. It should run the 9 strips softer at ~1470ma, with less watts but better efficiency. Compared to the 480h-24, I do sacrifice some room for expansion, as well as the ability to crank 9 strips up to 2000ma, but the 320h-24 is $40-60 cheaper and itās unlikely Iāll need to really expand beyond 18-20 strips or drive them that hard anyhow.
I still havenāt decided if Iād prefer type A or type B. I feel external dimming may be advantageous, but it also means more wiring and parts for drivers Iām probably going to remote mount. That wireless dimmer was neato, though I also worry about future compatibility regarding the app, and $100 for a hub/controller is a bit steep.
Yup, that will get you 320 watts total at roughly 35 watts/solstrip. They will run nice and cool at that rate with almost any heatsink.
Are you going to do two of those fixtures? You have around 16 sq ft of grow space, so 320/16 = 20 watts/sq ft. Thats on the low side as far as I understand it and a long way from your original 1000 watt target 
I agree, it would be good to keep the drivers outside the tent. They run very hot at full output - almost too hot to touch - and will add a lot of heat to the grow room. Plus they add a lot of weight to the fixture and can make it unbalanced if not positioned in the center.
For me, and how I have my space setup, there was no advantage to using a driver with an external control. I just mounted my 320H next to the tent where I can easily reach it to make changes in power out when needed - which isnt very often after I finished playing with it like a new toy
I also have my inline power meter mounted in the same place so I can see what power level Im at when I do make changes.
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I plan to run dual drivers, two identical 9 light strips, that should put me at 640W, ~41W/sqft and ~1200 ppfd (hard to tell without umols/sec for each strip).
I plan on mounting two strips per 2x34 heatsink, one from to each driver. The bars will span across the width of the room and be spaced evenly across the center 4 feet of canopy.
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sounds like an excellent setup to me. 
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This seems like a stupid question, but how does one go about remote mounting multiple drivers, and what wire do you use as the extension?
Also, if the umols/joule of the QB288 @1400ma are any indication, I should be expecting ~2.7umol/joule for a whopping 1720ppf at the board and 1150ppfd over 1.5 square meters 
Its really easy. You just use longer wires between the driver and the fixture.
The drivers come with short pigtails on the in and out side. If youāre getting them from Solstrips, he adds an AC cord to the input side and a waterproof connector with a short pigtail to the output side. You will need to provide extra wire to go from the connector to the solstrips no matter where you mount the driver. For remote mounting, you will just use longer, larger ga wires.
For the 320 series, I would recommend you use at least 14 ga multi-strand wire between the driver and the fixture. Id even go 12 ga for over 8 ft of wire.
After you get to the fixture, you will want to drop down to 18 ga solid wire for the final connections to the individual strips. The connectors dont work well with stranded wire at all! Regular, two conductor, 18 ga solid, thermostat wire works great.
I used 8 ft of 16 ga lamp cord I had laying around to go from the driver to my fixture inside the tent, and it runs slightly warm at full 300 watts output. I thought I was grabbing the 14 ga stuff, but I screwed up. I am still operating well below the max current rating of the wire, but I dont like warm wires and there is a measurable voltage drop. I for sure should have used larger wire.
One important thing I forgot when I was wiring mine up - dont force tooo long a piece of that solid 18ga wire into the connectors on the solstrip or you can damage them. Maybe 3/16" - 1/4" max!
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The plain english translation = they are very very bright! 
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Would Romex 14/2/2 be acceptable to use as an output extension for 2 drivers? Itās got 4 conductors and a ground.
Solid core wire would not be a good choice for the run to the fixture. You are going to be moving the fixture up down from time to time adjusting the distance to the plants. Solid wire is not designed to flex or bend repeatedly. The thicker copper will fatigue over time from flexing, and its resistance will increase. Thats why the electrical code requires romex to be fastened to the studs at a certain distance between staples, even when its behind a wall - to prevent any movement.
You could make it work, but you will want to mitigate flexing, sharp bends, etc. Maybe make a large diameter coil in the romex where it attaches inside the tent to when you raise/lower the light, the wire has as little flexing as possible. Like a coil spring.
You really should us multi-strand wire.
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You are ok with using solid core 18 ga wire once you are ON the fixture, because you will solidly attach that wire to the fixture at periodic points so it doesnt flex.
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Great, I can find 4 conductor stranded much easier. I knew Romex wasnāt supposed to be flexed but I also erroneously thought solid core was the better choice.
Another question: are optics a reasonable addition, and if so, which would be the recommended option? I am comfortable running bare but I also know that optics can really boost performance by directing the photons into a denser stream.
Optics? Do you mean lenses of some type or a reflector? I have never heard of anyone using lenses of any type. I would think they would be counter productive. Usually, the problem is getting the light spread out evenly across the room.
I suppose some sort of fresnel lens might work, but I would guess it would need to be custom made to fit the grow space and the exact dimensions of your light.
Some sort of side reflectors might possibly be used, to capture light lost to the sides, but the ledās are already somewhat directional. If your tent has reflective walls, I dont think they would be worth the trouble to fabricate and install. Plus you risk creating hot spots if you focus to sharply.
I think you will be much better served by just spacing the strips as evenly as possible, then adjust the height of the fixture, and power output, to vary the intensity at canopy height.
Here is a graph of the light intensity based on viewing angle for the LM651C
The Florence-1R-90 is what HLG recommends for quantum boards, theyāre clear polyacrylic (?) And have to be glued onto the board. Some say theyāre a pointless PITA if youāre growing in a tent/closet, while others swear by them.
I was thinking just going bare and hanging the light ~12-18" from the canopy so photons canāt scatter too far without crossing incidence with plant tissue. I hadnāt considered radiometric hotspots created by lensing.
Interesting. I cant tell if those are fresnel or not. I dont have a clue if they would be good, bad, or indifferent, but you would need to balance the losses in the lens (about 4%) vrs the benefit of the new light pattern. Nothing is ever free
Youāre going to be running at relatively low wattage, so this shouldnāt be a concern for you, but they might tend to trap heat and reduce cooling efficiency.
I guess if you have the budget, it might be worth trying them out.
Im cheap, and I have more than enough total light energy for my space, so I would just stay bare - but thats me
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I heard lenses if you use foliar sprays alot
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