Having recently left PA, joined as a graduate and left after two and a bit years there are a couple of things I might be able to add to the party:
1) Utilisation: Is not the be all and end all in terms of career, despite what you get told. If you are after bonuses etc then it is the way to earn the pounds.
However if you want to advance your career outside consulting a range of client experiences are crucial. I never would have got the role I now have if I had achieved 100% utilisation via being on one job for a year. Therefore I missed my utilisation target one year and just scraped under a year later, but worked for 9 different clients.
2) PA's Reputation: I was plesantly surprised when I started looking for jobs how many people had heard of PA. Plus once you are in the interview it is all about what you have done and how you perform not whether you
3) Make a Decision: If it is consulting you don't like then get on another career ladder with a blue chip quickly. I messed about for too long, ended up staying for 2 years (looking back this wasn't such a bad thing) but you need to think it through then go for it either way.
4) Operating at PA: It only takes one job, or a different approach for you to make your name in PA (due to the size) this can quickly land you in high demand. Try to get a role showcasing / if you help out with some research try to get a trip to client site (if in London) to deliver it.
5) Don't close any doors: There are many people who have left PA and come back...always and option