Need help asap! AP Calc Prep Book Decision 5 steps or Barron's?

I am currently studying and my prep book isn’t loading properly so I’m switching readers and I need to know whether to buy the prep book I’m currently using (5 Steps to a 5 kindle), buy a different one(AP Calc Barron 2013 kindle), or go out and get the most updated AP Calc Barron’s 13th edition. I’m tight on time (why I’m leaning toward kindle options even if there not the most updated) and studying for two other APs as well as SATs. It’s crunch time and I can’t buy a bunch of books I just need one good one and pronto.

Just get the Barron’s 13th edition. It has good reviews on Amazon.