Very nice thread, and interesting read (haven't read all the posts yet, just kimmed through the OP's posts). From what I can gather through the results, this thread more or less confirms that the "equivalent to 400w HID" is really bologna as expected, and that 90 watts is really 90 watts in terms of getting something like .5 - .6 GPW...
My question, I guess, is: what's the real advantage of growing with LEDs, if they don't really produce much better GPW's than standard, easily-available lighting options such as fluorescents and HIDs?