I couldn't find any difference except for the penetration issue ....I have 3 42w(150w equiv each) with 2750 lumens each and a temp of 2700kelvin..I'll be using these to light 1 square foot~(flowering) so I have 126W(450w equiv)with a total of 8250lumens....I'm well over the 50w/sf min and closer to the 10000lumens than the 5000lumens min needed...I have 4 strains started...NorthernLights #5,Skunk#1,BigBud and WhiteWidow...I also have 3 unknowns and 5 "MysteryMix".....I know the 3 unknowns are a southernQuebec indoor/outdoor strain but as of yet,unidentified...

I havent decided which strain will "volenteer" for the experiment but I'm sure one of the girls will be more than willing...the rest will be under my faithful 400's...