I use Sierra quite often, have not had any problems yet, have heard complaints from others about aftermarket lower unit gears failing prematurley, but have not experienced this personally and don't know if the failed parts were sierra or annother manufacturer!!
have also had some dealers, OMC & Bombardier,,substitute sierra parts for OEM parts and then try to charge me OEM prices!!
have also had some dealers, OMC & Bombardier,,substitute sierra parts for OEM parts and then try to charge me OEM prices!!