If you run your water through the pump body after your mixing valve, it's going to take a long time for the water temp to change when you adjust the valve and I think you'd find it quite annoying. Like oh water is too cold, turn on some hot, in 5 seconds the temp starts to change, in 10 seconds it gets too hot, turn the hot back down agian, repeat this process. If you were going to only use cold water this wouldn't be an issue and I could see it working well.