I thought the P1 required warmers. That was basically where I was going: no warmers.
One thing to watch out for it the change in profile if you go with the Bridgestone. Michelin and Pirelli both have a similar profile. I like the Pirellis.
As for the number of days I'll use them: two things: budget and riding style. I enter turns too slow and exit really fast and only use moderate amount of lean angle. This puts most of the stress on the center of the rear tire.
What I'll be working on Saturday and most of the winter will be entering turns faster. This will put more stree on the sides of the front tire.
The 2CTs I ran this year are now my street tires. The sides of the rear tire are toast, but the center still has some life. The front tire looks fine. but the rubber is grainy. These tires were used from February until October (about 8 track days + 1500 road miles).
The Pirellis will only see the track. We'll see how long they feel good for. As my pace increased I might have to back off of the 8 thing. Which stinks b/c that makes track days more expensive. I'd hate to have to buy a set of tires every month.