Didn't expect a 590

Hi,

I'm new to this board, but after reading some of these messages, I already feel a lot better. I totally didn't expect a 590 because I thought studied enough and my scores on practice tests were alright:
Kaplan Diagnostic 660, Cat #1 580, Cat #2 620
Powerprep #1 640, powerprep #2 730
The second one was taking recently, and I admit that I've done some of the questions on the powerprep before the test.

What surprised me the most is that the test was MUCH HARDER than I expected. I was hit with probability questions from the beginning, and my sentence corrections were paragraphs, none of those 1 or 2 sentence easy stuff. From reading the web, most people scored close to their powerprep scores, and posted that the real GMAT was much easier than the Kaplan cats.
My biggest problem is my time management on the math section (I was trying to do the hard questions in the beginning - b/c of how people said the 10-15 questions are the most important, and ended up not having enough time at the end), and I have to study harder on my verbal.

Anyway, I was wondering:
1) I've done the last 100 so questions of the DS & WP, all of the SC & last 100 of CR & RC in the OG. Today, I did 40 DS in OG in about 40 minutes and only got 1 wrong. I feel like I should be studying something harder. Is it worth it to do the rest of the OG?
2) I've also done most of the Kaplan 2003 CD - problem sets, and most of the kaplan books (i also have 800 & verbal) repeat themselves, so what else is there to do?
From reading your postings, it looks like PR isn't any good.

I want to take the test again in a month, and was wondering what's the best strategy? Any suggestions will be appreciated.