I took a pretty good spill and tweaked one of the arms. The phantom hardly hovers on it's own. I completly gutted the thing and put it in a new shell, but that didn't seem to help. The gps compass seem good. One of the motors takes a tad bit more effort to move, but nothing really obvious. I'm kind of out of options so I'm considering replacing the motor, even though I don't really think it's a problem. I know this has probably been discussed ad nauseam, but I couldn't find any previous posts. I have a few questions before I take the plunge. I'm really not looking forward to soldering this **** thing. 1)Is there a deterministic way to determine if the motor is good? Something more than does it feel or look like different? 2)How important is it that you replace all 4 motors? Can I just replace the one? 3)To avoid resoldering the motors each time they are replaced should I put bullet connectors? If so where can I get them? Thanks.