i using hoya super hmc and pro1 low-profile, and kenko pro1 uv filters.. but after some experience learned to remove the UV filter before putting on the CPL..
problem: hard to unscrew the CPL from the uv filter.. especially if you screw it on all the way.. ended up having to remove both filters from the lens, and twist and turn both pieces in a lens cloth until i can loosen it..
if you screw just one on the lens, its easier to remove..
It's wiser to remove the UV filter and attach the polarizer.
You are probably better of mounting the UV filter on most of the time, but hey, there's nothing to stop you from keeping the polarizer mounted, if, for instance, you are out shooting on a bright sunny day.