A couple of weeks ago I got the result from my SQL 2008 MCM Lab exam and I failed.
I have been working with SQL Server for almost 12 years. I have been a developer, dba and architect and last year I joined Microsoft to become a Premier Field Engineer on SQL Server. This means I have a broad experience with several aspects of SQL Server and since joining Microsoft I learned something new every week, if not every day.
So how did I prepare for the MCM Lab exam? Well I did not. And I choose to. I wanted to know where I stood. Talking to other people who were thinking of doing the MCM and reading through the materials I was not sure what to expect. And for me that makes it hard to prepare myself. Although one could argue this is exactly what you would do in real life, it just doesn't feel the same. Failing the MCM Lab exam made me more experienced. Every day I waited for the result I knew more and more what I did wrong and how it should have been done. So even though I failed I have learned a lot. I think you can prepare yourself perfectly by going through the material listed on the MCM site. I just didn't have to time to go through it although I did went through some video's. So in a sense I did prepare myself, but for me, everyday is preparation for the MCM. I get challenged every week by different customers, with different SQL Server setups and different challenges. Some are hard, some are easy, some bring up a lot of discussion and some are just a lot of fun but every engagement has made me more knowledgeable on SQL.
Of course I am retaking the exam. And the fact that I did not pass but did well, strengthens me in my believe that I can achieve this. But this time I come prepared. I know my weak points.This means I can develop a proper battleplan. I will watch a few of the MCM videos, especially those in my weak areas (http://technet.microsoft.com/en-us/sqlserver/ff977043.aspx). I will setup a lab myself an try out some scenarios I think are common or hard to setup. Being able to apply knowledge from experience will help you getting the job done.
I love the exam. It is so much more testing your skills then the "regular" exams. But then again, this is the master exam. If you are pursuing the exam yourself challenge yourself with peers, get a group of people together trying to achieve the same goal. And if you think you are ready, go for it. Worst thing that could happen is that you fail. But that wouldn't be the end of the world. You can always retry.