Middlebury is a good school. However it is a bad idea to go into debt for undergrad especially if you want to go to a top school for a MBA. The hassle to finance middlebury isn’t worth it, reputation doesn’t outweigh you taking the opportunities at UVM or St. Lawrence. Rule out Middlebury
UVM and St. Lawrence are good schools, UVM has a more well known name (arguably better than middlebury) but again that may not mean UVm is your answer. UVM is a mid sized school while St. Lawrence is pretty small. What size do you like the best? Also, UVM has an amazing college town and beautiful lakes and mountains nearby. I’m not necessarily saying st Lawrence isn’t nice, but I have been to Canton and it’s so rural. I personally didn’t like it, but you need to make the choice for you.
I personally love UVM a and I think it may be your best bet. You need to tour both and decide which you feel most at home at.