First let me start off by saying I attended a California community college, which are notoriously very good schools. The California CC system is basically set up for those who plan on transferring to the UC's or the California State U's. The transition is very smooth, and credits for lower division science courses are accepted without any trouble.
From my standpoint, if you want a good lower division science education, and you live in CA, go to a CC. I took Chem 1 with a class size of about 60, I knew the professor well and he was excellent. Compare that to taking Chem 1 with a class size of 500, in a stadium of a lecture hall, at a 4 yr university. My Bio 1 class had maybe 30 students. Classes were more interactive, you felt free to actually ask a question in the MIDDLE of the lecture without intimidation. And many of the professors, knowing full well that we planned on transferring to a UC, worked us like dogs. But man, we learned. By the time I transferred to UC Davis, I was scoring top grades in biochem, physiology, embryology, and microbiology (mainly because almost all of the material was already taught to me in my lower division bio class in the CC).
There was no trouble with schools accepting my CC credits. And the MCAT was a breeze. Remember though, I'm speaking from the standpoint of the California CC system, so it might be much different from community colleges in other states.
As for splitting up O-chem (yes people that's what we call it here in the West Coast), I wouldn't recommend it. Sure both classes cover the same material, but there could be a dangerous gap in between the two classes... and this material may be needed in order to build upon the principles and concepts you'll learn in the second semester. That is, you'd might have to catch up in order to NOT be lost the rest of the way through. Either take it in one place or another, but don't split it.
Best of luck in getting into med school. Feel free to PM me if you have any more questions.
Regards,
Nardo (less than a month away from being an attending---- boo yah!!!)