So, in your preference, you're like thing the MH Radiums, at least right now.. more so than the T5's...
I guess I really should say that I like the look of the MH Radiums and the T5s together. And actually, I do really love the dawn/dusk times on the tank. The time with just the T5s on is some of my favorite viewing time on the tank.
I like the look of all T5 tanks as well. My first 75G reef started that way, and I thought it looked good. And I might give this tank another shot with all T5 again somewhere down the road. If I do, I'd likely go with a Powermodule like you are considering. The one time I tried all T5 on this tank, I did not have a really favorable bulb combination to give it a fair shot.
On that, how did you attach them to a vertical surface????
Again, it's nothing more than super glue. A lot of it.