Interested in what SimonH (Hi Simon - we have met & talked on this subject) said that the sliding pillar can be made to work, sort of. Well I know it can actually be made to work quite well actually - though it took us over 2 years of spring rate and damper development and thousands of miles to optimise, ok there are limitations with stiction even with good bush material and lube - I think we all know the problems......
The race engineer who tested the Mulfab IFS and published the first article on it in MSCC Miscellany also road tested our 'mid development' rising rate spring set up. He rated the ride at least as good as the Mulberry double wishbone set up with no handling detriment on the road. (It was a normal road test not a track test). We have developed it further since for even better ride and less roll matched with a specially tuned damper.
This is a matter of 'horses for courses'. The geometry advantages of a correctly optimised double wishbone suspension are clear, but enormouse improvements in ride and roll stiffness over any factory set up can be achieved with a rising rate spring combination with a damper change.
Four well established English Morgan dealers and two Morgan specialists have driven the test car with the rising rate springs and tuned damper and all have been very impressed with the excellent ride, high roll stiffness, no bobbing up and down of the nose, no crashing through potholes and the price.
As they say, you pays your money and takes your choice. PJB.