Just thought I'd let you know my story from rainy England.
Having gained a First Class in BSc(Hons) Software Engineering I thought that this exam would be reasonably easy, and that from my degree I would have 70-80% of the knowledge already and would just need to brush up a few things. I soon changed my mind when I scored around 30% in a few mock exams I took!!
Problem for me was that my job didn't have a massive Java component to it, meaning that I had to learn most things by continually reading and testing (rather than doing). I also made over 200pages of 'flash cards' with key ideas on them, and took there wherever I went.
After 6-9mths of studying outside of work, I bought the bullet and took the test and was really relieved when I passed first time.
I still have mixed feelings about my grade - 69% (needed 59%). In many ways I feel that I've done well to pass first time without a huge amount of practical experience, especially when I read some exam preparation guides that said "be prepared to fail, many do". On the other hand, would have been happier with a little higher.
Since passing this exam, I have been to two interviews, both who have offered a job. The job I've accepted has a large J2EE content and the company has offered to train me. They also have a history of frequently supporting their employees through Sun Certification.
With this in mind, I've already got myself a copy of "Head First Servlets & JSP" and my eyes on getting a few more exams under my belt....