Premed classes will be very competitive and academically demanding at any of a wide range of universities (both daughters had majors that overlapped with premed requirements and so I have heard multiple stories). I would be surprised if there is all that much difference in terms of which of these two very good universities would be academically more demanding. You will need to work very hard and make a strong effort to stay ahead in your class work at either of them.
If it were me I would be inclined to agree with @bluebayou, stay in-state, and save my $$$$ for medical school.