advice on lighting, used mh or t5 glo

[megs_clark]

Hi. Im new to saltwater and have a 30 gallon bowfront that finished its cycle, now i need to upgrade my lights. I want to try some colorfull corals & fish, and need advice on what light to buy. Im on a bit of a buget. I was told by my local fish store to stay away from the compacts, and to buy a glo t5 ho. It had 2 bulbes, 24w each. Doesnt seem like much to me? My question is should i buy the glo t5 ho, or buy a used mh. I see them used from time to time around $150-$200, which is my price range right now. And the t5 is $140 before tax, so even in price. And if you think i should buy a used mh, what should i watch for. Are their good and bad brands? Do they have a lifespan on the ballast. I want something that will last me a few years. Hope for some good advice, thanks