You have the iPhone 4 right? If I recall, the flap for the dock cover on the Commuter flipped out to the back. It gets in the way of almost all docks. In my opinion, the Commuter isn't very well designed either. I sold mine to someone else.
I use the iHome IB969G Charging Station for iPad, iPod, iPhone, BlackBerrys and eReaders. Got it on amazon for under $40. Fold the flap back and it charges no problem. Dock cool. Charges iPad and other stuff all at the same time.
I use the Seidio Inno Jr. dock, and it should work for just about all cases. Easy to insert, and the connector pin moves forward to make it even easier.