I remember being in an argument about this once in the old mecha thread, (too lazy to look it up though). Things to consider though, OT reaction engines probably have high thrust values, lack of aerodynamic drag in space means you don't need to burn to move forward which means you save your fuel (which is possibly stored in some exotic pressurized tanks, like what's being developed for hydrogen powered vehicles) for maneuvering.
Personally though, I'd rather not go into length about it, gotta think about the poor catgirls.