We don't normally recommend them on this board. The stainless ring does offer a performance increase because of tighter tolerances... but if you suck a rock into the pump, it will cause more damage, since there is no "Give" in that ring. (and they are expensive) With an OEM ring... a rock will gouge the ring, but it will probably not destroy the impeller, and the pump shaft, and honestly, if you are careful, the plastic ring will last for 5 to 10 years.