I just purchased the Wrangler case from Ivyskin (The best selection of Smart cases, and accessories for iPhone 4 / 4S and iPad 2 iPhone 4/4S Wrangler Case Only at IvySkin USA SmartCase® store), I really like the look and protection of the case. However, the finish on the case makes it very slippery. I was wondering if I would be apple to fit a bumper over my case to provide extra grip?