Well, I *think* I made the final decision on my lighting today. I'm going to go with 8x39w Icecap T5 retro. 4 bulbs front to back, on 6" centers, over each half of the tank. The Icecap ballasts overdrive the lamps to 60w each for 480w in total. This comes with the Icecap reflectors too, which are among the best available.
I was all set to go with 3x 175w Iwasaki 15k bulbs in Lumenarc reflectors, but changed my mind. Those particluar bulbs put out a ton of PAR (more than 250w Phoenix 14k), but are very white and I would have needed to supplement them. I really couldn't see having the halides plus a bunch of supplements.
I have a used but in good condition Lumenarc III that I don't need now...