I've always been happy with the plain Jane sureflo on/off pumps that have been in my RVs. . BTW, they have a screw to adjust the pressure.I also use an expansion tank. I put a loop in the discharge line and I have that loop suspenders with lightweight rope so it can't hammer against anything. I've wrapped foam around about a dozen places where lines hit floor, wall or anything else. I only hear a very slight rumble when the pump runs and there's never any rattle or thumping. Craig