If you are up for a long read, I think you and others might find http://www.americanaquariumproducts.com/Aquarium_Lighting.html">http://www.americanaquariumproducts.com/Aquarium_Lighting.html</a> interesting. He is in business to sell the TMC product line, but I know of no other vendor that has done as much research, to support his position, as this guy. He has positive things to say about some other brands and makes it clear that certain TMC fixtures are not appropriate for certain applications. What I really like is that when he says a certain product is right for a certain application, he tells you why based on the science.
Although I'm not sure I always understand what I'm reading, I have done extensive reading on this subject and listened to countless "opinions" and find it interesting that in all the threads on the subject, there is rarely anyone that quotes any scientific research to support their position, even though this is a subject based entirely on science.
I guess LED's are still new enough that it hasn't dawned on some people that all LED's aren't the same and that there is no "one size fits all." Manufacturers like Cree produce LED's with a model name that stays the same, even though the quality of the emitter has changed over time. Just like car manufacturers keep a model name year after year, but you wouldn't compare today's version to one made years ago. So you may buy a DIY Cree XP-E thinking it's the same as the XP-E being used in a high end fixture, when in fact it is old technology. And to make things even more difficult, the difference between cheap LED's and the old technology of the quality lines appears to be huge, not to mention the new technology. It blows my mind when people buy cheap Chinese LED's on EBay or in a Group Buy thinking they are getting the same quality in terms of PUR as the high end lines provide.
Just saying...
