With the recent purchase of my first smart phone - the Samsung Droid Charge - I wanted to make sure it was adequately protected. After looking around at the options, I went with the OtterBox Defender.
The OtterBox Defender contains a polycarbonate frame and screen protector, which is then wrapped with a silicone cover. It also contains a belt clip so you can have the phone on your waist instead of in a pocket.
I was concerned about the frame, as it covered portions of the Charge's keys on the front. While I may to position my finger just right and apply enough pressure to have a key press, it's not as bad as I was afraid it would be.
The screen protector is not noticeable at all. Interacting with the phone's screen is like the protector isn't there at all.
The silicone cover covers all buttons, ports, and keys. Space is left for the microphones, speakers, cameras, flash, and light sensor. The tabs covering the USB power/accessory port, earphone port, and HDMI port open, allowing easy access to the ports. On the back, part of the frame that surrounds the camera, flash, and speaker is exposed. This removes any resistance provided by the silicone cover, so the phone can slide around easily - for better or for worse. Plus, as the cover covers the keys, it also covers the light they give off when turned on. This hasn't proven to be a big deal for me, but may for you if you try to fumble around with the keys in low light. The silicone cover gives the phone a nice, solid feel.
I thought that I might want to use the belt clip instead of carrying the phone around in a pocket, but I have decided not to use it. Like the leather belt clip case, it can feel odd having that big of a phone on my belt, plus I already have my FitBit there. Having the phone there as well would cover my pocket and I prefer having stuff on my right side. Additionally, it was too difficult to get the phone in and out of the belt clip case that comes with the OtterBox Defender. I don't want to mess with that when I need to take a call, make a call, or do something on Android.
Another option is to go with the OtterBox Commuter, which does not come with the belt clip, but uses a film for the screen protector instead of the built in protector. Even if I knew ahead of time that I did not want the belt clip, I would still go with the Defender, as I prefer not to use a film for screen protection.