I ran my 10 up until this Christmas on NO; I had two 27w 6500k screw in CF bulbs, two 18" 15w tubes(actinic and 6700k) and one 15" 14w 18000k(or so it was called); 96w total. I grew palythoas, mushrooms, some hitchhiker LPS, chaeto, various macro algae, and a ton of Coraline with no problem, so it can be done, in theory at least.
Here's the other side:
1. that was on a 10 gallon with a custom canopy. on a larger tank, you might not be able to fit enough bulbs for sufficient light, and I highly doubt it would work on deeper/higher tanks(mine is only 12")
2. at Christmas I upgraded to a PC fixture; two 40w bulbs. I'm saving electricity(80 vs. 96w), have a good bit more light, and the colors are simply incomparable. Plus, the fixture cost me $100 brand new; prior to that I spent close to $80 in ballasts, endcaps, bulbs, etc
if I had gone with PC from the start, I'd only be out around $20. On a larger tank, NO would probably actually cost more. Plus what I have now is a MUCH better solution.
I'll post before/after pics tomorrow, but right now it's 1 am and I have class at 9.