Guess it all depends on space you gonna use for your grow. I grew 2 under my 400w and they came out beautiful, I`m growing 6 now and theyre ok but its a bit of a overkill without LST or supercropping as bottom parts are geting virtually no light. I`m definitely switching to 600 for my next grow though. You know, you can even grow 20 under it but the point is to give each plan as much light as possible so I think growroom size(or the ability of particular light to cover whole grow area) is the most important factor. And dunno how are prices in US but that seems kinda pricey for what it is, no?
