The case provides a secure way of keeping the phone. I now routinely keep it (inside the case) in my trousers' pocket together with keys and coins and the phone is well protected at all times. At first I was slightly disappointed because the case doesn't have a belt clip, but I find that keeping the phone in the pocket works perfectly well and therefore serves me very well.
Before using the case I used to have a knack for touching the "Cancel call" button accidentally when the phone rang. Nowadays the case prevents me from that silly mistake, since I now have to open the case after I grab it from my pocket and only then select the button to deal with the incoming call.
Finally the looks: it feels classy as well as practical. It looks good, it is robust and you have access to all the buttons available on the phone.