K&B book is enough to prepare for the test. I did some projects and read the book three times and get the almost same result of the test provided in the CD-ROM, 85%.
For preparing time, it depends on your experience and the time you can spend on it every day. You can try the CD-ROM test after you have read the whole book, if you get a high score, that means that you are ready for the test.
Best Regards,<br />DongShan<br /> <br />SCJP1.4, SCWCD1.4