So final update.
Only when I got tyres replaced did I find the tyres that looked relatively new, with plenty of tread were also in fact manufactured in 2010. When I showed the sidewall defects I was told it was not pothole damage, so god knows how it got there.
Anyway the final result was an incredible transformation of the ride of the car with new tyres. It is so much smoother and compliant a ride. I had misinterpreted the harsh ride before to be all the fault of the suspension setup, where in fact although suspension needed tweaking the tyres had a large part to play.
So £215 well spent on 4 new Avon ZV7’s (plus fitting). Result
