Aloha Charbud.

You asked:
"Any advice on purchasing ?"

My unsolicited advice?

Look for high-power emitters.
1. and 2W. leds are a bad choice for blooming.
(For reasons see "penetration misunderstood" on the IC.)
So, avoid Hydro-grow, UFOs, etc.
StraightouttaWeed is using lights with 3W. emitters that are blooming up a storm.
I have yet to see any commercial lamp hold a candela to my homebrew 15W 660s. but his come close.

Weeze, out.