Hi Steve,
As you've already said, its a how long is a piece of string question. I think some people could do it in a month, if they were already knowledgeable and some a year. The best way to figure out if you are ready to take the exam is by taking the test quiz on the CD. If you can consistently pass this test, then (certainly in my experience at least) then you are very likely to pass the exam.
Good Luck!
Brian
MCP, MCDST, MCTS x 4, MCITP x 2
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