70-297 Preparation

preparing for 70-297, anyone who has sat this exam any info on how long required to study for this. I have complete 294 does all the main technical knowledge carry over to 297. I am reading Sybex so far. Any feedback will be appreciated.
Comments
* Upgrading from NT4 * Migrating from NT4 to 2003 using ADMT * Business structures (for example, cost center) * Administrative/resource structures (centralized/decentralized, for example) * Forest Designs (Why you would isolate data into another forest) * Domain Designs (Why you would create a second domain in a forest and not just create another forest) * Why have an empty forest root domain
Good luck with 70-297