I would like to get a case for my Blackberry Curve 8310 to cover some of the scratches. I looked on Amazon and a lot of the cases said "for Blackberry Curve 8300/8310/8320. So I was just wondering if these were interchangeable? For instance, if I went to Best Buy to buy a case, could I get a case that's for a Blackberry Curve 8320 and it would fit? Or do I have to get a case that says specifically Blackberry Curve 8310?