I tried all of them and I thought by far the best and longest lasting in my opinion were the xray ones.
But I HATE paying that much for them!
So I have since gone to the smokem steel outdrives with Tamiya shafts, which come with bearings and spare clips and pins for $35 a PAIR.
These seem even smoother than the xray ones and the bearing is 1mm skinnier for more steering. the benefit of running no plastic boot on the outdrive side means less maintenance too! Very happy with this setup!