hey Man, nice to see you back around here!
Well, you'd better stick around than!
Looking at a seller's page on ebay constitutes "research", like me taking a first aid class makes me a doctor. It's all a bunch of bright colored text, mixed font size, bad kerning, and unbacked information. He backs up not one of his statements. There's an old saying "Extraordinary claims require extraordinary evidence.", this guy makes alot of claims that blow every other LED out of the water regarding output theoretically. If this man actually had a 50w chip that put out that much light, he would be making alot more marketing it through a real business to governments and just about every place where bright light in a cheap manner would be wanted (Read: Everywhere!). In short, if "Sun Master Kami" had actually revolutionized the lighting world to the tune of a 700%+ increase in lumen output, he'd be making billions in the market as it exists. The man wouldn't be selling one or two on ebay (I combed through the last 300 reviews he got, he gets good ones, none regard his 50w chips though.), he would be making a profit that makes an ebay store trivial and pointless. Think about it for a second, the seller doesn't quite add up reasonably. Nobody likes to get ripped off, but it happens to us all. I could be entirely wrong, and am more than willing to be. However, first you need to substantiate your claims of how awesome they are. If I dropped $350 on a light and got ripped, I'd be hesitant to accept it too.
Kelvin is also for visible use. It is the color that a black body radiator appears to the human eye at that many degrees kelvin. A spectral power distribution graph is the only way to judge the actual spectrums of light that are produced by a bulb, and therefore it's actual usefulness for growing.
