[Christ]

I'm still doing some research on exactly what needs to be done to make it work correctly, and I don't have a controller yet, and they're not the most efficient motors in the world, but if you have 20 of them laying around, it's probably more efficient to drain the batteries a little faster than to spend good greenbacks on a motor...

Brushed motors need maintenance far more often than non-brushed type motors, also... so the efficiency is a tradeoff with maintenance, to some degree.