HPS 150w question

I'm thinking about purchasing this light: http://www.bghydro.com/BGH/itemdesc.asp?ic=HLCSHPS015SS

(150w HPS with ballast in the hood, only 71 bucks.)

And I'm gonna build a grow box for it. But my question is if I go into Home depot and purchase a metal halide 150w bulb (if there is a 150?) would it work on that setup.(since hps is mainly for flowering) Any info would be appreciated, thank you.

Unless it's a switchable ballast that uses mh conversion bulbs, I wouldn't try it.Just use the hps all the way through. I did, it worked fine.