I'm a first year at Mayo, so I can only answer some of your questions.
The class schedule during first year is usually 8 - 5 (with 2 hours for lunch) 2-3 days a week, with the other days being finished by 11am. During 2nd year the students start clinical rotations M-F during the am and have classes in the afternoon. I like our schedules, but I do learn well in lecture.
Your match list question is definately related to the small class size. First of all, most schools have the most matches to their own programs. The residency directors know their own students from rotations, so they know what they are getting by ranking their own students. Also, if you like the system and school you trained in, you'll likely want to stay there for your training. In addition, many of the MN residents want to stay in Minnesota for residency, but prefer to go back to the Minneapolis/St. Paul area. Lastly, no matter where you go to school, your grades and scores are what is going to allow you to apply to powerhouse residencies, if that is your goal.
I like MN winters, but I love snow and winter sports. I think the average high temperature during the day for the winter is in the mid 20's, but it can get much colder. However, with Mayo's tunnels and skyways, you can stay indoors when it gets real cold. If you are coming from the south, it will probably be a shock. I wouldn't let the weather be ther reason you decide not to come, because we have awesome weather during the spring, summer and early fall! I really enjoy having 4 distinct seasons.
I didn't apply to Vandy, so I can't give you any comparisons to their programs. In the end, you need to pick the school that will fit your learning style best. Congrats on having such a great choice. I love Mayo, and I am so lucky to be able to be here!