I fitted the Mulberry bearings some years ago, and suffered from terrible wheel shimmy. I found out this was because my car was set up with 4 degrees of castor angle rather than the 6 degrees on later R&P cars.
I refitted the damper blades and the problem went away.
When I went to the Suplex system I kept the damper blades and all is fine, and like Andy I'm a convert. Getting the correct setup takes a bit of effort, it's true, but I think it's worth it. I also think that it seems to suit better if the car is run with a low ride height, i.e. with the spacer below the stub axle.
I would say if you are not getting shimmy problems with your current setup, you are unlikely to experience it if you fit the Suplex kit.
