After following SBM around
Yes, I too was mightily impressed when I saw how well Steve's car coped with the backroads of Northamptonshire and Lincolnshire.
I am pretty tempted myself, but since I fitted 4-leaf springs, panhard rod, anti-tramp bars and AVO shocks back in 2011 my car is pretty well-behaved at the rear end and with only 165bhp to keep in check it's well up to the job.
But I think for a Roadster or Plus 8, I think it would make a massive difference.