My wife and I bought the sf4000 for our first indoor grow to extend our vegetable growing season. We got the light last wednesday, today is the 5th day and there is a huge difference already! We are growing Kajari melons in a 4x4 tent. If you are wanting a high quality light from a great brand, then look no further. I spent hours reading reviews and contacting growers who posted reviews using the "other" brands. I can tell you one thing, the owner of this company does not have to bribe me with promises of huge discounts or being sponsored with free lights for a great review. The product speaks for itself! In fact, we plan on buying another sf4000 soon to grow lettuce/herbs in a different 4x4 tent.
Oh, I almost forgot, an American small business with an 5 year warranty to top it all off!