About 30% of guns in my survey had soft internals. However, that may be low, as many TLA owners have never shot their guns or haven't shot them enough for bad parts to show themselves. One of my #5s had soft internals. Three of them I haven't had checked. The fifth was checked and was okay.
Any good gunsmith can check them and fix them, if necessary. By good, I mean someone like Dave Clements, Alan Harton, Bowen, etc.