I have a 54g bow,, which may be the same footprint. I bought a canopy that is nothing but a fake fiberglass rim 9" high: it supports (just sitting catty-angled atop) a single light kit that has two ballasts, one for the 2 actinics, one for a single mh 250 w bulb: I use a Reeflux 12000, which gives nice blues while promoting growth. (you run actinics to 'blue-up" the otherwise garishly yellowed light of an mh, and actinics stay on 12 h a day, while the mh should be run about 6h)---
My tank is about 20" deep, easy reach for a hand with a razor blade to clean the glass (once I take off the 9" fake rim canopy---which also prevents fish jumping out)---
With a 250, if your tank is significantly deeper than mine, you would have a lowlight bottom and would keep high light corals only on your upper rockwork. As it stands, I have to shade lowlight corals like bubble. I do not know about lateral spread, if your tank should be somewhat wider than mine instead of deeper.
I do not know the brand of light i have: I bought it here in Spokane, and I know my store does some shipping. It's got a fan at either end to cool the fierce heat of the bulb, a glass protective bottom, and contains the 2 actinics and the single mh bulb. the single huge cloth-covered cord bundle exits one end and becomes two cords, one for the mh ballast, one for the actinic ballast. I vaguely remember that I spent about 800 on lightkit and ballast and about 300 on the canopy/rim. The latter I thought really excessive for a plain shell with no top in it (you don't want to cut off air flow on a marine tank) but it has proven one of the best decisions: it prevents jumps, makes handling my light kit during cleaning pretty easy---I just shove it back; and it looks spiff, providing a 9" black top facade to the tank that makes it, with its black stand, look like a piece of furniture...while, of course, serving to shield the eyes from that brilliant light.
The mh bulbs are the ones that produce the wave-sparkle on the sand and rocks. Crocea clams and some acropora corals demand that much light: it's too much light, say, for zoas and probably for some mushrooms. And you DO need a shield like my rim for that light, or it will be blinding for somebody sitting in the room, say, watching telly.
There is a thread somewhere (maybe in the equipment forum) about T5's. They can keep most anything. I don't know about relative price.