I got a 26Q (ouch!) on my first Kaplan test, at the beginning of my study. I took the diagnostic test in the OG after a couple of weeks and got 29 out of 48 (60%) right, with 5 careless mistakes. I haven't taken any more practice tests yet, but based on my success with the timed practice questions, I'd say right now I'm probably around a 38Q.
I worked through the whole OG Quant Review book, which helped, and which lifted my success rate on the Problem Solving questions. Still, on the hardest Data Sufficiency questions, I'm only getting about 50% right and sometimes timing out. I took a breather and went through the OG Verbal Review, and found out that I just need a little work on Sentence Correction. Now I'm going to hit the Kaplan Math Review.
I'm not as concerned about cracking 650 as I am about having a really weak quant score that sticks out. A 42-43Q score would do me just fine. I've got five weeks till I take the test, so I'm hopeful I can get the job done.
I'm going to check out the
Manhattan books, thanks for the tip.