Let me first say that except for spontaneous activation, I've mastered PRing.
With that said, I think that if your CPA is coming up soon, it might not be worth using PRing yet.
I know that as far as math goes, the CPA is probably the hardest test of its kind. Actuaries, though, I've heard make a decent amount of money, so it can be worth it.
Despite what is said, PRing can't give you skills. You can read a book on how to increase skills faster than anyone, but unless you practice it, it's useless in that respect, really.
I know that you said you passed the first four exams, so congrats on that =)
But if the last two still have some tougher math like derivatives and integrals, then reading more might not help you.
The reason I say it may be a bad idea, is because right now I think you need to practice practice and practice on your problem solving material, and given the time it will take to do that, it might not be prudent to try to learn PRing at the same time when the little it will help you on is nonmath material, and even then, if you're having trouble with PRing, and haven't gotten the system down in time, well...
...the bad experience could very well ruin your life.
So, I know a lot of people may say differently, but in my honest opinion, I would concentrate on all the different tricky wordings of math problems they're going to give you, take a lot of practice tests, and worry about PRing after you pass the six exams. PRing will help you in life outside of tests, and will still be helpful to learn once you become an Actuary.
Good luck, sir. I'm sure you're dedicated enough to do it.
-Ramon http://razor.ramon.com
