Our Plus Six had the SSL upgrade last month undertaken by Williams. The result is a much improved ride and it feels ( to me ) that handling is also improved. I can not say that the upgrade would help prevent buckling of 19" wheels. I suspect the major factors would be determined by the shape and depth of the pot hole plus impact speed. I have not noticed a difference in ride height, but I have not undertaken any measurements, as our Plus Six has never badly bottomed out, even two up and luggage onboard. We are due a ferry trip next week, so it will be interesting to see how it copes on the ferry ramps.
