James,
if your car still has an OPC warranty (and has 19" wheels), then to maintain the warranty, the only Michelins which are N-rated are Pilot Sport 2 (PS2).
From my experience would have the Michelin over Pirelli any day (rain or shine).
If you are going with the Michelins (either the approved PS2 or even the PS4S), would just bite the bullet and go for all 4 at once as mixing manufacturers front to rear not a good idea as the balance of the car will be affected (and also would void any warranty).