LOL... haven't seen a question like this in a while. FWIW, here's my opinion, but remember I'm an old non-trad: the material in medical school is not difficult - you proved you could handle it when you were smart enough to get in. The problem is the volume. I'm sure you've heard that going to medical school is like drinking from a fire hydrant, and it's absolutely true (example: block 2 was metabolism in my biochem/genetics class, and we did an entire semester of undergraduate biochem in less than six weeks - in more detail). Yes, you can have one evening a week free in the first two years (and I recommend it for your sanity) - but plan on working on all the other afternoons and evenings, weekends included. It's a big culture shock - your days of being the smartest kid in the class who starts studying a week or two before the exam are over. Not studying is absolutely fatal in med school - everyone studies (or lies about it or flunks out).
Guide by year:
First year. Not too hard, but you're not used to medical school. For me it was the most difficult year - and, looking back, I wonder why. This is when you'll learn to study. You will also have gross anatomy and a cadaver - which is not as big a deal as you might think it is, but I'm glad it'll be you and not me - been there, done that.
Second year. Harder than first year, but the material is less pure basic science and more about sick people, the reason you went to medical school. You'll know what you're doing and you'll know how to handle things. I never went to class. All in all, not a bad year - I sometimes miss having so much time at home with no work to do except studying.
Third year. New ballgame. You're in the hospital and the clinic, and you're expected to be on-time and look respectable. Just when you start to feel like you've mastered a rotation, it's time to move on to the next one. You will still study lots, but now you have to do it at night on your own time, and there often isn't much of that. Exam at the end of each rotation. Some rotations you may have one free evening a week, but others you won't. You'll learn to be a doctor this year. Tough, but very rewarding.
Fourth year. Mostly electives. After working like a dog for three years, people tend to act a little surprised when you show-up where you're supposed to be on-time. Residency applications, interviews, and board exams are stressful. Other than that, 4th year is your reward for having survived medical school and it's the last screw-off time you'll have before becoming an intern, when you will once again be tortured.