OEM axles are far superior. If you an, reboot, or rebuild the joint I you have to. Many stories over at tdiclub about vibrations with aftermarket. Even if you don't have a tdi, the point is the quality of the shaft. If you have to get up and running in a hurry, buy a NEW aftermarket shaft assy from Advanced Auto for $90 with no core charge. KEEP YOUR ORIGINAL and rebuild it when you have time.
Yes, my aftermarket has a vibration between 1800-2000 rpms.
Correct most after market ones tend to cause vibration issues but on the good side you can return it back for full refund if it's under lifetime warranty. Mine only lasted a year and started giving me issues and vibrations so I return back to local parts store for full refund. Grab the axle on the ground with your hands at each end and twist, if you feel a little free play than that's what causes the vibrations. luckily I had the original oem axle still available to compare with.