<p>SIR–statement of intent to register—
You have valid questions. You might post them on each cc site (UC Davis & UC Berkeley) to get feedback from current students, and grads.
Most agree with alansda that it might be more difficult to get into UCB over UCD, and their admission decision might make the choice for you…but if both come in w/an acceptance…then you are indeed faced with a need for a clear decision.G’Luck.</p>