Jerl, what bulbs are you running now? I have worked with T5 and MH in numerous situations and while I love a good halide, T5s are far superior in the fact that you can fine tune the color of the tank so that every coral pops. As far as growth goes, I don't think you can top the right halide over a good tank (sorry LED fanatics, I'm not ready to drink the koolaid) but that isn't to say that in the right hands you can't get respectable growth out of T5s. I personally like to mix my halides with T5s for maximum effect. My most recent show tank has a 400w SE ushio 14k (love it even by itself) and 4 2' HO Geissman T5s, 2 actinic+ and 2 pure actinic, placed one on each side of the halide since it's a cube tank.
I find that the best tanks with T5s have several different spectrum bulbs over them instead of just 2 or 3.
You also have to remember that light over the tank is cumulative, so if you aren't using lights that are as bright or have the same kind of par you just need to leave them on longer.