A few friends have been growing in soil, under lights.. Usually they grow a few plants for personal use. Each one has different specs,ie; lights and types, and combos of hps/mh during veg + flower plus different nutes. All the guys have ok yields for what they are doing, tho one mate has been using only a 400w hps/mh and his buds take longer to mature and bulk. I suggested a 600w so it offers more light thru the canopy, cos he cant have big setup, would the 600w produce larger flowers,denser bud over a bigger space than the 400w or would buds be similar in size just longer to mature? at me.. lol.