Interesting to hear a first hand account, Ian and surprised you think there is so much in it versus the MPSS.
I'm actually just about to commit to buying a set of Michelins for the 997 to swap out the P Zeros (N2).
My only quandry was whether to go for the 4S or the Cup 2s... The Cups have the advantage of being N rated if I go for a 305 on the rear (standard width is a 295 on a 2WD car but the widebody cars weirdly are fitted with 305s also on an 11J rim so I expect should be fine )
Bearing in mind how cold and wet Britain can be is making me think twice however...
Oh and if anyone wants to buy a set of 10% worn P Zeros let me know.