I'm looking to get a shell for my XL so that I can feel good about shoving it in my pocket, etc. However, I've heard stories about how they scratch up your 3DS when you clip them off or take them off and that's something I don't want to happen. Which case should I trust? I had my eyes on http://www.eachmall.me/goods-16157-16157.html but it looks like it could be one of the ones that scratches when you clip it on. Any thoughts or suggestions? Doesn't have to be aluminium either, btw.