I'm by no means the best person to ask but ... 3 cxa3070 3000k on 3 arctic alpine 11 fan/heatsink combo with some 13$ eBay drivers is the defacto standard... That's 150 watts(I believe)of cost sensitive action!!! Good luck mang!I love this post and this information is pure gold. I've got a smaller tent - 5 sqft- i'm super concerned about heat and a bit cost sensitive, can you (or other forum DIYers) recommend a 3 COB setup for me? i'd be much appreciated