CMH with Parabolic hood?

So long story short. I am building a 3x3 room but it only has 5 1/2 foot ceilings so I am only going to grow bushy indicas for now. I plan on getting a 315w CMH light. So my question is.
Should I go vertical hanging, vertical hood, horizontal hood or parabolic? I can get the light into the rafters if needed for extra height but I would rather not. The space will actually be 5x5 but with 3x3 flood to drain growing area, room for fans and what not.

You could scrog two plants and grow horizontally up, but you'd get best spectrum spread I'd guess with that parabolic hood relection.