i took the DAT test before w/ the total score of 16, i was having the topscore but then it was sad because all of the materials stress u out but when it comes to the test it wasn't that hard, those questions are very simple, i was wishing that i have spend more time cuz i have only done one practice exam from the acethedatdotcom and i think it's easy and closely related to the test especially to those biology (17, i guess, i dont remember anymore) chemistry(18), organic(18), math (14), pat(14) cuz i didn't study them until the last minutes i guess
i brought the topscore but then my computer got virus so i only finish one exam from them, just kindda bad score and i didn't study from that test much but from the first practice exam, i just think it was too hard, harder than the real DAT, after that i switch to acethedat. i think their practice tests are pretty good
but i dotn think they have good explaination
i dont know about the achiever though
good luck to you and to me
cuz i'm planning to take the DAT again, but probably in summer when i have times to review