They are a bearable ride.. much softer than a rigid.. if the axle is inline with the springs, they work fine, the offset axle mounting, IZ can not speak to that as I have not used that type.
I put a lot of miles on a Saviour, and long rides, was happy with it. Handled fine, but I am not a roasdracer, nor try to be. I do remember surprising an unexperienced Norton rider on a twisty road with it...