I don't recommend that one. It doesn't have individual parabolic reflectors. For T5 to be worth it, each bulb needs it's own reflector, and they're usually about 2.5" wide each.
If you're looking for a budget fixture, you could go with a sunlight supply new wave fixture. They're new and aimed to be a little lower budget. They only have a single ballast though, and the 48" 8 bulb units are hard to find.
if you're looking for prices, check j&l
http://www.jlaquatics.com, and call Gold's aquariums. Even better, go in and talk to Albert personally. Gold's usually has great prices, only you have to wait sometimes if they have to order it. Great service there. Highly recommended. *thumbs up*