When I changed bodies, I had to update some of my accessories too.  My old filter system was fine on a cropped body but with full frame, the filter holder encroached on the corners for the wide angle lenses.  I took the opportunity to change my polarizer set up.  I used to use a polarizer on my Cokin holder.  This was a bit inconvenient when I was using lens hoods.  Instead, I decided to get a screw in polarizer.  Since most of my lenses have the same filter size, this gives me more flexibility.

I took the polarizer with me on vacation.  One place where I made good use of it was in the rain forest.  While it was pretty dark in the heavy forest cover, there was moisture everywhere and this meant a lot of reflections and glare.  Consequently, I went with the polarizer most of the time.  While I was there, though, I decided to do some experimentation by repeating some shots without the polarizer to see how much of a difference it made.  You can see the with and without shots here and judge for yourself what a difference it makes.