They're honestly quite comparable. I got into both as well. This data is making me move toward davis over UCI though:
Davis has ~573 million vs 300 million for uci in research expenditures, ( a sign of the universities financial viability.)
Davis has ~800 million dollars in endowment vs 200 million for UCI.
Davis is going up the ranks a bit faster than UCI (not a huge deal, but still)
Davis seems to have more school spirit from what I can tell, not as much of a commuter school.
Davis is 42nd up from 44 and uci is 46 down from 44 on USNWR (I don't care about this, but because other people do you might have stronger applicants favoring davis over uci on the basis of this silly rating. This actually means the rankings do matter, in an indirect fashion ( potentially stronger students preferring UCD).
That said UCI is definitely a great school and is stronger for other sciences I believe. With UC system being so taxed financially though davis seems like it will likely fair better than UCI ( although it's only UCR UCSC and merced that really have to worry).
You'd probably excel at either school, I heard both are good for pre-med.