TLDR; Whichever is cheapest, fastest and easiest to obtain a high GPA for med school admission
Last year I actually spoke to a doctor who went to UCLA for undergrad before he attended medical school.
The one thing he told me was: If he could do it over, he would’ve gone to whichever school provided the easiest and cheapest route to obtain a high GPA (which is a major factor on admission into grad school).
I’m not saying that she shouldn’t choose UCI, but I will say that the UC’s tend to be more difficult in terms of achieving a higher GPA because of the quarter system and grade curves (where your grade is based on how well you do against your peers).