[MrForbes]

The small CIMs definitely win for drivetrains.

We have very little experience with the other motors, but did spend quite a bit of time analyzing them while deciding which to use to run the arm.....and ended up using the Banebots motor with a 36mm 125:1 gearbox. The fact that it appears to have been designed and built to be used in robotics applications is a BIG plus, the shaft is designed to put a sprocket on, and the gearbox has several sets of mounting holes. The problem is that you need to have a good appreciation of the fact that it is relatively fragile inside. You can't expect to get a lot of torque out if it (10% of rated stall torque is about the practical limit), nor have it survive repeated full power back-and-forth motion. If you use the banebots transmissions, you must take extra effort to design whatever it is that it actuates so that the transmission is protected. Also the motor will quickly smoke if you put power to it when it is up against an immovable load, so you have to make sure the system is designed with some failsafes.

(thanks to the kind folks here at CD for informing us of all these limitations, so we learned the "easy way" instead of the "hard way"!)