- This is just my opinion so take it with a grain of salt and obviously do your own research
First you have a lot of cheaper options compared to that $1300 SK that neither lists what type of chips they are using other than "cree" or in what ratios, if you claim it you better be able to back it up. Cheaper options can easily be built from scratch or bought as basic diy kits from places like solstrips or cobshop and the likes.
Why would one buy said light though, either they have cash to burn, or were suckered in, i'm not saying they probably don't work well but here is something to consider design wise.
Single point light sources vs multiple sources.
Single point sources have only a couple of advantages, less units to hook up and you can grow at greater distances away from your light due to the intensity of said light but with stipulation i'll get into. Disadvantages though are a more condensed heat area, if it breaks your screwed, can't grow as close compared to a less bright source, light intensity will reduce the further away from center you are, and some things ill list below.
Multipoint, if you have enough units your light output will be the same given the same area, but coming from multiple points your plants will be more evenly lit and hit from multiple angles where as with a single source some areas will get shaded out and you have to relay on straight penetration to reach those. If a single unit fails you can still continue on. Wider flexibility in grow area dimensions as you can place the lights to fill your space how ever you want. Being spread out also reduces concentration of heat and intensity so you can get the plants closer to the lights which is beneficial in limited height situations.
Now why wouldn't a person just run a lot of screw ins instead of a big light ? Need to consider picking the right tool for the job, and what may be easier.
First have to consider the area you want to light up "even if you haven't built it yet" or more specifically how much yield are you looking to get over what span of time, as the really more dictates what one needs. But is hooking up say 6 lights is better than hooking up 50, but depends on the need.
Also if high quality components are used they will be more efficient than screw ins as ones built for cost and one for efficiency what are the end costs, and does an efficiency reduction really hinders you ?
Not to make this too long and prevent me going off on tangents i'll leave this post as is and we can discuss further in subsequent posts.