Stainless wear rings are a huge improvement over the stock ones. SeaDoo is the only manufacturer that uses non stainless ones. Being a full time PWC tech, I work on SeaDoo, Kawasaki, Yamaha and Polaris PWC's daily. Generally, when rocks go through the SeaDoo pump, you have to repair the impeller and replace the wear ring. On a Kawasaki, Yamaha, Polaris, Tigershark etc. you only have to repair the impeller. My machinist does an incredible job at repairing impellers. He makes them look like brand new.
nvmopar, if you want, I can PM you my phone number. I do mobile PWC repairs and I have several customers in West Vancouver and North Vancouver.
Chester