AAMC is the best indicator...that has been said many many times. even the people that complain that the real MCAT is way harder than the AAMC tests still score within their AAMC range a large majority of the time.
i took as many AAMC tests as i could so that i could get a range of scores, and my final score fell within that range, maybe even a lil higher. I took Kaplan tests, but didn't pay attention to the overal scores b/c too many have said that you shouldn't go by them. I took them as practice problems so i could get better at reading passages, etc. etc.
I'd play close attention to the AAMC scores.