Buying cases for iPhone 4

Hey everyone,Was just wondering about the new iPhone 4 issues with the signal cutting out when you touch the black strip on the side.I know they've just released that they will be giving all iPhone 4 owners a free case to fix this problem, but I wanted to know if you have to use the case they give you or if you can buy a different one?Example being I always wanted to buy a fancy rhinestone cover for my phone, but they are made of plastic not rubber, so will using one of those still fix the signal issue or does it have to be rubber like the one they are giving out?Any help or suggestions would be great Image may be NSFW.
Clik here to view. View the Correct Answer Buying cases for iPhone 4 in iPhone errors Correct Answer , iPhone 4 errors Correct Answer