Kind of depends on what you want to keep, what matters to you and what size the tank is. :wink:
If looks (the appearance of the fixture) matter to you and the tank is small, I'd recommend going either with a single MH pendant or one of the newer LED fixtures. That way you get decent punch and shimmer. If the tank is larger and not deeper than maybe 24", a T5 fixture would be your best choice, particularly if having actinics matters to you.
Let us know the broad outline of the set up you're thinking of (fish only, reef tank, what sort of coral, what size tank, what your priorities are).