Just like the question says.

 

Depends on the shape of your old pads, what caused you old rotors to be bad? how many miles are on the old pads and what shape do they look like there in?

 

doesnt hurt but i have done it many times i go through a set of rotors here in germany about every 6 months but it doesnt hurt

 

If you dont your a cheap and silly. They will wear your rotors uneven as the pads are not "true" from being used. Buy the pads, or you will regret it. I was told by the guy who taught me to work on cars "there are 2 things on a car you never cheap out on, steering and brakes."

Q

 

Its rather unorthodox but since I had almost new pads and slight warpage in my rotors thats what I did. Mine stops fine.

 

Your rotors and pads wear together. If you have a groove in the rotor you will have a groove in the pad. Putting a pad with grooves on it on a new smooth rotor, obviously, is a bad idea. Ive always been told it is a no-no.

 

Brake pads are cheap, unless you get performance ones.
I second the opinion that brakes is not something you want to go cheap on.

 

Perfect, thanks guys.