I bought this tire to replace the horrible Bridgestone Potenza runflats that are the OEM for this car.
What I noticed initially was the abundant wet grip. These tires stick almost as well in the wet as my Bridgestones stuck in the dry. Driving here in Germany, especially on the Autobahn, wet grip is important as is the ability to push water out of hte way and keep from hydroplaning. The PS3 meets both needs in spades.
Dry grip is very good as well--also very communicative. Initial turn in is a bit off...takes the tire a bit more time than I would like to get settled into the turn, but once you feel it bite, you can start to dial in a bit more power and change steering very easily.
I am very curious to see what the treadwear will be on these. Due to the higher grip, I think I have been driving them a lot harder than my old run flats--definitely a more fun drive! Also, they are VERY smooth at speed. I have had them up at 155mph for extended periods and they never wander and are very stable. Road noise is very good as well.