I use the Valterra adjustable PRV set at 50 psi. The flow regulators in the shower head are a mixed blessing, they restrict flow while hooked up to campground sewer and water, but when boon docking are valuable to help conserve water and grey tank capacity. I have no problem running out of hot water even with a rather long shower, largely due to the restrictor in the shower head.
Ole and Anne Anderson, Highland, Michigan
'02 Adventurer 32V, Ford F-53, ours since 4/08,Goodyears, Konis, SeeLevel, CHF
'84 CJ-7 , 5.3 Chevy, 3" lift, 33's, Detroit Locker, Fiberglas tub, winch, hi-lift