Did I Get The Wrong Motor?

First a little background. In 2009 I set out to build a 72 volt lead acid battery powered motorcycle. At that time the Etek motor was no longer available. So I had three common brands to choose from not counting the D&D which I call the Blue Motors. So the choices were the $2,000 dollar LEMCO, the $1,000 dollar Perm PMG-132, and the $500 dollar MARS ME0708 or ME0709. I ended up buying the ME0709.

Since then I decided to settle for a 48 volt system (for now at least) because of difficulty I was having shoving 6 batteries into my bike, and more importantly cost. For example you can land a used 48 volt golf cart controller for $150 where a new 72 volt one will run you three times that. I say new because golf carts mostly come in 36 or 48 volt configs, that I have seen anyways so most likely you are forced to buy a new controller to build a 72 volt system.

Anyway my question is would I have been better off with the ME0708 as it revs up higher at 48 volts?