Hi,
I have 5 years of experience and it took me about 3- 4 months to prepare for CISSP. Exam was very tricky but if you know the material well, its doable.
Resources used:
1. Eric Conrad Study Guide 3rd Edition - Highly recommended.
2. Kelly Cybrary ( Both Videos and Mp3)- Highly recommended.
3. Sybex study guide 7th Edition - Completed only about 70 % of the book. Nicely explained concepts.
4. CC Cure training videos - A very good resource.
5. Shon Harris Mp3 - A very good resource.
6. CBT Nuggets - Keith Barker. A very good resource for last day revision and motivation.
7. This forum and Cissp Study group on facebook.
Practice Tests:
1. CC Cure.
2. Sybex Test Bank and review questions.
3. Eric Conrad practice test and review questions.
It really helped me a lot reading/watching/listening from multiple sources.
The best way to judge yourself to see if prepared to sit for the exam is by referring to the glossary of your preferred study guide. If you are able to understand and relate each each term, then you are ready.
All the best

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Thanks,