We have a shower that was installed 9 years ago that the valve started leaking on, apparently Kohler has not changed the design at all because we purchased this and were able to replace the "innards" of our existing valve with the "innards" of this new one and it works perfectly!  In general we're pretty happy with the price/reliability of Kohler.  9 years of heavy use for a valve before it started to fail seems pretty good.