PSGM has a plasticky coating that starts to peel away after around 6-8 hours of play. Once the coating starts to peel the internal fibers are exposed causing the string to soon thereafter break. You'll know the plasticky coating is just starting to peel because there tends to be a bit more build-up of ball fuzz on the PSGM. I haven't noticed the same plasticky coating on PPA and the playability seems to be the same, just a bit more durability. I'm going on around 20 hours of play now with PPA and still no peeling or breaking.