I use an Otterbox Commuter as well.
Typically, I'm happy enough to go naked. I carried my iPhone 4 naked for over two years. Every case, even bumper and slim line cases always made it feel too bulky to me.
But the iPhone 5 is way too thin. I tried a bumper case for a while and didn't like it. Then a slim line and that didn't work out. The Otterbox, surprsingly, felt really good, provides great protection, and gives the phone some much needed bulk. The major complaint I have about it is that ridiculous cutout on the back for the Apple logo. No one cares. I've started trying to look for some similar alternate cases that doesn't have the hole. And I'm thinking about cutting the rubber cover off the bottom that covers the lightning port.