I have looked at both. And even though I haven't started studying, TPR looks a lot more appealing. If you follow the class schedule (PM me for one). TPR is also known for some good overprep. It's not concise like EK, rather it touches up on everything in detail. And just something about it (prbly its ethos in the test prep market) makes you feel more "at-rest" psychologically. It sounds weird, but I look at it like this. If you were to buy a new laptop, offering 2 different ones at the same price with the same specs, would you take a Sony Vaio or a Toshiba? You would prbly take the more well-known brand. It just makes you feel better when studying, and it may help you not doubt yourself when you begin studying.
I have been researching what books to get for a while now, like you. I evaluated a lot of things, and I decided to just use TPR. This is just what I choose, but you can do whatever you want. But the general consensus on the forum is:
Kaplan: Stay away (however, they seem to have decent topical tests)
EK: If you are crunched on time, get this. But it is concise, which may or may not help. The Audio Osmosis is exclusive to them and nice if you are driving a lot and have time to listen.
TBR: Great for content review. Great depth, recommended by many, and is the content focal point of SN2ed's schedule.
TPR: My review of choice. Very neat and organized. They conduct a $2000 prep class using the same content books you can get from Amazon for $120. It just seems more trustworthy IMO. Plus seeing all those 36+ scores on the Study Habits thread from people using TPR is very reassuring.
But it all comes down to what is best for you and how serious you are going to be during study time. Content is only one part of studying for this exam. The most important thing is, and no one can stress this enough, is practice.
Just FYI this is what I got:
Content: TPR hyperlearning set, Using friend's old EK (Bio especially)
Practice: AAMC 3-11, 101 EK passages, might get the 1001 series from EK, have 3 Gold standard tests too
I heard TBR is really good at the Chem and physics, but I took those courses seriously in HS and college so my background is strong. Again, it's all about practice tests, go to the library and see what they have. That way you can use everyone's practice tests without paying.
Hope this helped! Good luck.