I'd say both offer very good protection however it's a little more in favor of the Commuter. The Candyshell is a nice case however it's known to have an issue with the rubber flaking off as well as the case being a scratch magnet.
you should be fine if you get the new design. to be honest i think both of these cases have some flaws and i would look around and makesure you get something thats going to hold up.