Well here are my practice test scores:
http://forums.studentdoctor.net/showthread.php?t=873878
I didn't record tests 5-7 on Achiever since by that point I was close enough to the test that I was just wanting to learn as much as I could...in hindsight I should have done this before shipping off my laptop with all the software.
Below are my Achiever vs. Real. On average around 4-6 points more on the real than achiever.
Achiever AA: 19
Real AA: 24
Achiever TS: 19
Real TS: 24
Achiever QR: 22.25
Real QR: 26
Achiever PAT: 17.75
Real PAT: 23
Achiever RC: 17.25
Real RC: 21
Achiever Bio: 17.75
Real Bio: 24
Achiever Chem: 18.5
Real Chem: 26
Achiever O-Chem: 19.5
Real O-chem: 22
EDIT: I should add that my scores in tests 5-7 were lower than the scores on 1-4 since the difficulty curve in achiever tests just increases with each test. So maybe my scores are even more disparate than I am capable of informing here.