The key thing they said is that the AVERAGE pressure is 78 pounds. At times it could be much higher. I would feel better with a pressure regulator valve. Note, this modifies your water system, and will create another situation that needs protection - if there is not an expansion tank on the inlet to the hot water tank, then one of those would need to be installed at the same time.
A prv makes your water system "closed". ANy water that comes into the house cannot go back out. Now, you'd ask why should I care. Two reasons, it keeps any potential polution you might create (hose in a puddle and the system hiccups sucking in some water) and the hot water heater. WHen you run hot water, it gets replaced with denser cold water from the town supply. A PRV blocks water from expanding back out to the street. It has to go somewhere. Since water doesn't compress much of any, it will spike the pressure and often dump a little bit out of the T&P valve (temperature and pressure) on the water heater. This valve is just doint its job...keeping the pressure from getting too high for the device, but is very annoying. The expansion tank gives the system room to expand when required, keeping the pressure in check.
The prv has springs and seals in it. It acts sort of like an automatic valve to adjust the pressure on the inside of the house.
You can set the prv to whatever pressure you want, unless you have pipe sizing or restrictions, you should get essentially the same flow as you have now. I'd probably set it to say 60 pounds. Many people with pumps live with much lower pressure.