Clansman Dynamics uses large spherical roller bearings and taper roller bearings throughout the range of machines.
One competitor uses PTFE spherical bushes. Another competitor uses a mixture of needle roller bearings, roller bearings and steel spherical bushes.
It is worth noting that one large Italian foundry which has destroyed a machine from one competitor and which has 4 limping machines from another has made a campaign change to replace spherical steel bushes not with PTFE spherical bushes which would have been a straight swap but has machined new parts with larger bores for roller bearings.
There is no denying that manipulators present a severe test of any bearing because of shock loadings, dirty environment and the fact there is not much more than a 90 degree movement on any joint.
However some facts are known: