Taking a different route of tyre changes - I took our 2000 4/4 4 Seater on SS wires in for a new set of boots. Off came Yokohama C-Drive 2 in 195/60/15 and on went Toyo R888R's iMedium compound in195/55/15.
The drive characteristics were like night and day.... the stiffer sidewall of the Toyo's giving much more communication of what's going on without it being harsh - I found the Yoko's squidgy and the a bit bouncy at times. The tyre doing the work of the suspension and not in a good way.
Drove from High Wycombe to Liverpool and am very pleased with the swap. I might consider putting a 205/55 version on the rear to slightly up-tyre the back end to the original rolling radius - but that's just fiddling.
I can well imagine that it would be a great improvement on a good road. The roll centre would be lowered too. It would be a disaster for me however; speed humps, and even getting in to my garage, were difficult enough with the standard 195/60 and that is why I went 195/65 15 which raise it 1cm. To drop down a centimetre with the 195/55 would be great on my favourite twisties but I wouldn't be able to traverse some towns or get back in to my garage without tremendous scrapes on the cross member under the gearbox.