Slide-out jack stabilizers. Good or bad?

What do manufactures say about charging batteries at 14.8 volts or equalizing it 15.3? they say your converters good enough energy to do everything as built you don't need to do anything to it. from reading up so many post it seems like a lot of stuff doesn't always go by the manufactures recommendation. I have a fifth wheel that was manufactured with 15 inch marathon tires it now has fire stones 16 inch. Also has an axle/spring flip. Battery box was enlarged from two gp24 to four gc2. Compensated by moving the spare tire crank up to the opposite side from the battery pack to rebalance. Not one size fits all by any means when it comes to RV's.