Like the man said, you'll hear it even if its a holley black or blue pump....but when the music starts, all is fine!
Now then, theres something about filling my crankcase is diesel that rubs me the wrong way, so I always block off the Mech. pump, run a good electric, wired into the Hobbs switch plumbed into theoil system just below the stock oil pressure sending unit.
That way if you ever loose oil pressure, your fuel is cut off.
Best to have plenty of pressure though....its hard on the IP if you don't.....