I would absolutely suggest to do SN2 over any prep course. You need to learn how to sit down and study this crap. Its not like you are going to get prep courses for all of your exams in med school you know? You will have seen everything that could possibly be on the test (through undergrad). All you need to do to supplement it is by getting a hold of the examkrackers math and verbal strategy book which teaches you how to do MCAT math in your head. I took the princeton hyperlearning prep course and I never felt like I wasted more money in my entire life. The thing is that I know I personally went in expecting that they were going to teach some "magic" MCAT strategy that would help carry me through and really give me that leg up on those poor suckers who couldnt afford or werent serious enough to take a prep course. I could not have been farther from the truth. I realized that the best way to do well is to just do mountains of practice problems. Thats how the folkes in med school do it for the USMLE and COMLEX, thats how pre-meds should study for the MCAT. I wish I had known instead of burning 1500$. You have to just sit down for 8 weeks and do hours and hours of practice passages under timed conditions. Go through all of your answers in detail to figure out any holes in your knowledge. Do tons of full passages to get your speed down. Thats it.... It just takes hundreds of hours of dedicated time where you are beating it into your head. The passages will get easier, you will get more stamina and speed, and then you are ready. Fun, crazy strategies that Princeton and Kaplan come up with market really well, but in the end they take away from what you are doing - taking a test. Just practice a lot, then take the test.
Now my rant aside, the books that Princeton uses are really solid - they are not as deep as like Berkeley, but in ways that is good. And they are not babied down like Kaplan or Examkrackers. So get yourself the Princeton hyperlearning books. Get the 101 verbal book from EK, and get the math and verbal strategy book from EK. Do every problem in every book and do all of the AAMC practice tests. That is all that you need.
However, if you do choose to not heed my advice (as I would not have a couple years ago because I thought I knew best and was brain washed by friends who were taking prep courses), I would agree that the TPR prep course is better than Kaplan is so many ways.