I've grown with all kinds of lights. CFL, Screw In LEDs, Flourescent tubes of multiple types, (T8, T5, T5Ho, PLL (which is bent t5s) ) and i've never had these kinds of nugs. Density, trichome production, size, and all around fast plant growth.
edit: oh, and multiple HPS (ranging from 70w-600w)
If you aren't looking into leds, you should. Specifically Solstrips. The cost per watt is right at or under 1$ per watt, and you don't have to change bulbs, they don't fade over time, are better on your wallet both upfront cost and running costs. Heat management is simple, most setups would be fine in open air unless you're really driving them near max.
All in all, I paid 506$ or so for my 10 strip array start to finish, and that gets me the ability (with proper driver of course) to run 480w. Of course I'm not running them that hot, but it's nice to know I could.
Actually, IIRC because I went with the HLG-320H-24A, my final cost was only 400 or so, I found the driver cheap on ebay.
The real amazing thing I noticed, and I mentioned it quite a bit earlier in my thread. There are much less shadows under the leaves when using strips like these. They have so many light point of origins that it penetrates the canopy and even the lower buds while smaller, get very dense as well.
If you're on the fence, don't be, come on over and have some beer an chicken! Get yourself some high quality affordable leds man, your plants will thank you!