60 psi is nice, but...... Most RV's are labeled 45 or 50 PSI max, the reason for this is SOME, I stress SOME RV toilets, the seals in the fresh water valves are only rated for 60 PSI, you hit 61 they can rupture,,, this is when it is new, USED that 60 might be 55.. So i would not go more than 50 PSI (Nor do I even if my system has been tested to higher pressures).
It is not so bad when a kitchen fitting blows a seal, you KNOW that is fresh water, but when you blow one on the toilet.......... HAZ MAT procedure is invoked cause you do not know.