I use this one and so far no complaints. Phone slides with ease and the tabs that "grab" the phone to keep case on do not interfere with slide motion. Tried the hard rubber one from sprint and the tabs stuck up to far and rubbed on screen part of slider. I even tried to shave them down with a razor but it was to a point if I shaved anymore the tabs would fall off.
http://www.bestbuy.com/site/olspage....=1218049006120