Last weekend I finally passed the exam, with 78% Not the best score, but well above "just scraping through" so I'm happy with that.
I first bought the study guide in 2008, but procrastination of reading it got the better of me for a long time.
I prepared for around 3 months prior to sitting the exam, which gave me enough time to read the study guide properly, take mock exams, and panic.
Some tips for the exam :
If you're really stuck, use the strikeout feature to eliminate the answers that are obviously wrong, then sit and ask yourself which the remaining two could be right.
If the question has a lot of code, chances are they're trying to catch you out, so watch for noob errors like final variables being reassigned, final methods overridden, or interface methods overridden but not using the public modifier.
I used both enthuware and whizlabs. Enthuware was definitely the better tool, my whizlabs full edition expired so I didn't get to use it during my 3 month cramming period.
Write lots of code! Take lots of mocks, and don't forget to take breaks.
I wrote up more bits and pieces on my blog if anyone is interested