I've been using Ceramic metal halide 400watts for veg because they perform better that normal 600watt metal halides. Also after veg period I've been using Philips 600watt hps greenpower for flowering a 4 x 5 area, in my opinion this has been the best combination that I have came across and I have been growing for years. Well here's the kicker,,,I've recently purchased the 240watt Blackstar
VEG model with 2 and 3 watt chipsets, just to see how it compares with my CMH for vegging. Being a cynical kind of person, I am now eating my own words of doubt about led's, this 240 led is fu**ing unbelievably good at Vegging, I ain't seen anything like it before, I'm gonna bite the bullet and buy 2 of the 500watt flowering models to see how they perform, very exited, oh just a little note about these led, the 12000k whites in them peak at 440Nm,,,, even higher output than blue led's. Work it out