I know some people get bad axles from auto parts stores but you could get a brand new GM axle and have the same exact issue. So to me it's a crapshoot either way.

That said, I've always bought new axles from napa and I've personally never had a bad one. We owned 3 ponitacs at one and did 5 axles between them with napa parts. I choose to save some money and new axles have warrantys from napa.