[Lil' Lavery]

The advantages are numerous and pretty well documented in this thread and eleswhere. I highly encourage you to go with 4 CIMs in your drivetrain, especially as a rookie team.

One downside that hasn't been mentioned so far is weight. Adding two CIMs adds around 5 lb.s to your drivebase. Never forget the weight limit. That being said, it's some of the most productive and well placed weight on your robot. Keeping as much weight as possible down low is always a good option.