The curriculum is arbitrary, as in the way they present the information doesn't matter, since you're going to learn it regardless. But learning that material is incredibly important for all aspects of your education. You have to pass tests, do well in courses, do well on Step (which comes directly from doing well in the first 2 years) and then impress on the wards.
Your time on the wards will consist largely of using or assimilating the material you learned in the preclinical years. What is expected of me on a daily basis has far more to do with the things I learned the first 2 years than what I have learned in third and fourth year. That basic medical knowledge is the foundation of the rest of your education and is vitally important.
To be honest, you don't learn or do a whole lot in third year, and I think that's fairly universal. At UT they are very much focused on student education and make sure we always see and present patients and get hands-on whenever possible, so I think I'm even speaking from having a great clinical background at UT, but even so, the vast majority of the pimping and presenting and day-to-day management of patients relies heavily on those preclinical years. Yeah I can get to the OR and impress them with my suture skills or I can present the hell out of a patient, but knowing what's going on with your patient and how to manage it (what's expected from you as a student) comes from what you learned in the preclinical years.
Don't get me wrong, the clinical years are important, but you don't really learn medicine in the trenches that way. You do learn the practical application of the fundamentals in clinical years, but it's not until residency when you learn the true clinical side of medicine.
So my view looking back on medical school is to go somewhere that you'll enjoy, which is where the students are happy, where the faculty are supportive of the students, where you'll enjoy living (close to family vs far from family, whichever you prefer), and if possible, somewhere that's convenient for you as a student, such as a place that doesn't have hospitals 20-30 miles away that you have to travel to. Medical school comes down a lot to convenience, such as how easy it is to get to/from required attendance lectures or rotations, minimal interference with your study time, and so forth.
This is just my opinion, and you're free to disagree. I do see a lot of things that premeds get hung up on that I've found to be irrelevant to my education, though, and I'd hate for somebody to pass up a school where they'd succeed for the wrong reasons.