Also, consider which T4 school is a better fit for you in case you do not transfer.
I transferred from a T4 to a T2(70s). I finished number one in my class, but I NEVER felt like I had "mastered" the material; Law school is so completely different that I think it is worthless to plan on finishing at the top; instead, plan on committing yourself (100%) to learning the material (a lot of trial and error first semester). Then, you should be in good shape. But, do not get discouraged if you don't do as well as you "plan."
Also, be careful not to get sucked into others study habits. This will be tempting b/c you are going to make some great friends your first year.
Anyway, grades are, IMO, pretty much the key to a successful transfer.
Some other things to watch out for, some T4 schools "grade" harder, harder than T1/T2; maybe to keep transfers low, but I don't know.