OAT achiever was good for getting the timing part down for me... achiever seemed a lot harder than the actual exam to me though as far as the material covered. Just don't let achiever stress you out days before you take the exam thinking that you'd need to know all of that... the test is def. tough-but I found achiever much worse!
I found the MCAT kaplan book really helpful for the entire exam; def the bio, chem, and physics portions. A GRE math portion book may be helpful for the QR... Just read a lot of science journals and experimental papers to get your brain geared up for RC. I'm sure you'll do just fine since you're asking questions now!