Probably not a good idea to use a water cooled motor for combat. What motor you need depends on what its going to be doing, but the way you worded it tells me that your going to be using it for the drive. In that case, a simple cordless drill works well, look for the cheaper stuff or if you want to splurge on the good stuff, go with Dewalt. If your looking for a weapon motor, again, depends on what its doing. If its going to spin something, brushless, if its going to lift something, brushed.
