Here are my tips regarding potentiometers:
- Use the best quality pots you can get - 0.25$ pots wont perform as well as the 3-4$ pots... it's a small amount that's worth it.
- mount the pots securely making sure they cannot move.
- pots should not be load bearing parts. use them in a place where they will not be damaged by the load applied to your robot.
- remeber that if you need accuracy it is best to use a small gearing system that should make the pot turn more, that way you are minimizing the effect of the looseness in the pot itself.
that's about it I guess.... good luck!
-Leav