P1 is a doddle, although i managed to get roughly the same mark in it as P3 (the dreaded june 2003 paper !), which is scary. The transition from P1 to P2 is big in terms of the number of trigonometric identities you have to learn, but the integration and differentiation is a joke. P3 seems very easy when you're learning it from the textbook, but just wait until you do a past paper / the P3 exam, and you'll be in for a shock. In my opinion the textbook does a VERY poor job of teaching connected rates of change, which invariably comes up in every P3 paper for 10++ marks. P4 is pretty straightforward, P5 is very easy until you reach the Coordinate geometry and P6 is very easy compared with P5; the only fairly difficult chapter being the proof by induction, which if you don't 'spot', you won't be able to do.