I too am interested in this. I have a 1992 Plus 8 with 205/60/15 tyres , which are in good condition but aged. I would like to replace with a premium tyre that will improve the ride quality but not at the expense of grip. I do not drive fast (but like to accelerate and listen to that beautiful V8 talk to me) but I have always taken the attitude that no matter what fantastic gizmos any car is bestowed with, it all comes down to the couple of inches of rubber between all that performance and the thing you want to stay most attached to, the road surface.