I have a few. I use one in a 5x7 space in an open room. Run it up to 400 watts at about 30". Nice wide coverage, tight node spacing, just really a great light for veg. I run another in a 4x4 tent. This has been a learning process, power/heat. With my ambient room temp of 78-80 I have real heat issues over 400 watts. I am changing some things up and adding co2 bags. Man, I don't have a decade of indoor experience, that said, 400 watts in my setup produces flower that I can be proud of. I like the 600 at lower power than say a 350r since I get better coverage and have the ability to step up output, when needed. Call it "headroom". Now, I had a driver go bad after about six months. I looked international to purchase a replacement, expensive and not many available. Hey warranty. Sent email, they sent replacement quickly, back in business. Oh, the first one I bought I didn't care for the " delivered " quality of the heatsink. I sent pictures and pointed out my issues. They sent another one. Their packaging at the time was not up to par. I doubt they are the only dudes with this level of service and performance, in a competitive market place. Hope this helps and grow on with your bad self. PS, if you don't have a par meter or some form of measuring par, get something. Really helps me in setup and during my entire grow.