Www.skinit.com question?

I bought 3 cases that were customized for my blackberry phone thinking they were hard cover. Unfortunately when I did some more research I found out they were just Stickers LOL. Are these skins any good and do they last. I like to put my phone in my pocket a lot and if I am reaching in and out I don't want a $30 dollar sticker to come off. I mean is there any protection or true quality to these things. I spent a lot of time customizing and putting effort into it and if they come off after 2 days thats really bad quality and highly overpriced for some STICKERS. Hopefully they last a good long time and protect my phone in some way :D. Can someone give me some answers to these things. Thank You very much! :)