I'm a science department chair at a college prep school. There's no real easy answer for you, sad to say. A few things to consider:
1) Do the colleges you are looking at accept AP Bio credit? If they don't, you'll likely be repeating your AP Bio course again once you get to college. On the other hand, if they do, it's a good way to earn college credit you're going to need.
2) Do you want to take Physics for the first time at the college level? In general, college professors/grad students (who often teach the lower level classes) aren't necessarily good teachers. Some are, yes, but for every good one there's at least one bad one and a bunch of mediocre ones. Even with a good teacher, you might get stuck in a big lecture hall with 100 other students if you go to a larger college, so that's something to consider as well.
At the high school level teachers have more time for individual students and are generally at the very least decent at teaching, and most are fairly good if you want to learn. I teach both introductory Physics and AP Physics at my school. In my intro physics course, we probably cover about 50% of the physics material you'll see on the MCAT down the line. As for AP- by the end of the year students in my AP course could take the physics MCAT and pass it without having to work too terribly hard at it. (not that any of them are going into med school, of course)
I strongly recommend that students majoring in any science should have at least one solid year of bio, chem, and physics before graduating high school. If you were choosing between AP Bio and AP Physics, I'd say go for AP Bio. However, if you have to choose between AP Bio and introductory physics, I'd advise getting some physics background before heading to college.