Shower reculator

[Cajun]

I've seen shower recirculation on newer campers. I was thinking about adding one to my camper. Anyone have one installed in their RV?

I see 2 possibilities for this (correct me if I'm wrong) 1. You don't waste water by waiting for it to get hot at the shower. 2. You can send hot water to the fresh water tank if it's cold which helps keep it from freezing.

On #1. I think it's a given and it's intended purpose. On #2 it's just me thinking out loud, does it hold merit?