I got a new shell today for my P3. I also have a P2 and bought an extra shell for it a couple of years ago but never used it.
I was surprised at how much thinner the P3 case is compared to the P2 case. P2 case is almost twice as thick.
I have a couple of minor cracks just starting one one leg of the P3 so I ordered some Plast-Aid today to try it before going to all the trouble to change the case out.