For those of you that have it, does it move the mirror when you press the buttons? Is the mirror stiff enough to not move around when pressing it?

If the mirror moves when you push the buttons there is something wrong. here is their contact info

http://www.gentex.com/contacts.html

No it should not. Some of the earlier models (pre-2006) have smaller shaft and tends to be moved with less effort. The newer mirrors (2006+) have thicker shaft and are much more sturdy.

http://www.wembleysells.com/mirrortech/mountarms1s.JPG