I agree with Adam! Mecanum drive is very interesting, and you would learn a lot by making a robot with it. The problem is that one thing you would learn is that most other robots will be able to push your robot wherever they want to.
Our team made a mecanum drive robot for promotional use (we bring it to fundraising events mostly), and to learn how mecanum robots work. It is very educational, fun to drive, and people like to watch it. If the 2008 game requires a nimble robot that can go any which way, then it might be a good choice to use a mecanum. If you need to be able to push other robots around or to keep your robot in one place to score, then it would not be so good.
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