The typical problems I had with the open tops, both Pietta and Uberti, has been the paw spring breaking (have an original 1858 with a broken paw spring right now) and the soft steel in the cylinders peening where the stop comes up. I actually have a tool to clean the pocket up after each use. For the paw spring you can replace it with a Ruger style plunger and spring, then they seem to last ‘forever’. SASS is really hard on the guns because of the speed you are running them at, or at least for my guns.