We have been on the road fulltime for 2yrs and 3 months, it has been stated several times about replacing the Thetford toilets and the black tank flush valve underneath the sink. As of date we have had no issues other than turning on the water to flush the black tank abruptly and causing the valve to leak, if it is turned on slowly allowing the valve to seat and pressurize we have had no issues. As for the toilet we have not had any issues either, although we always turn off the water to our rig every time we leave for more than an hour.