[AndyB]

The drawbacks of swerve that I've experienced are:

• Harder to control from a driver's perspective (when compared to a regular tank steer)
• Generally heavier and require an extra motor for steering
• More complex to design and build.
• More expensive.
• Don't do ramps too well.
• Robot turning issues if you drive all modules together

If you are going to do a swerve drive, build one in the fall first. Get your practice in early. The hardest part in this process could possibly be to opt against a swerve after the game is announced. Don't do it just because you feel obligated.