We usually recommend the 48-V2+ for 48" long tanks as the 32s are a bit short for full coverage. With the 32" photon mounted 12-18" off of the water you will have coverage in most of your tank.
Thanks for the reply. I would also recommend the 48" v2 for my tank. I should clarify that I am married and my wife recommends not spending any more money on the tank. Hahahaha. I'm sure she'd be open to you all sending us a until though. Seriously though, I appreciate the feedback.