lighting a cube

I am planning my next tank. I know for sure that I'm gonna go with the marineland deep dimension 150 gal cube. It is 36x36x27deep. I was originally going to go with all T5's but am looking at MH's now due to the cost of T5's. I wanted to get some feedback on whether or not I could get away with 2-250 watt MH's or if I needed to step up to 2-400's. I also will have a few T5 actinics as well as moonlights. I plan on having a predominately SPS tank and plan on going with a shallow sand bed or possibly bare bottom. Any suggestions on lights, fixtures, bulbs, etc would be greatly appreciated.
Thanks in advance

 

I would use one of these
with a 400 watt ballast and bulb