Need quick help with 8 3/4 rebuild kit!!

.........R these new gears cause if no u r gonna have a gear whine that u may or may not b able to live with....the back lash on factory gears is prolly .030 and setting them up from where they were is big trouble.........kim....

My rear end guy recommended used gears over new gears. Didn't mention any problems and it is my only option for 3.23s in a 741 as they are not remanufactured. So are you saying all used gear sets will whine?