[JohnFogarty]

Pros: Strength and better long term reliability, No chance of belt or chain breaking or becoming misaligned.

Cons: Cost is vastly higher I would imagine, Weight would for sure be higher, and Gear drives need to be constantly lubricated. Gear drives can also be very loud. I'm also pretty sure that creating the plates that the line of gears would have to mount to, depending on how you did it, would have to be precision machined.

Most of my FTC drives were all gear driven, but I would imagine FRC gear drives would be very much more expensive. My FRC experience is limited to Belt & Chain so you'll have to wait for someone with more expertise to come alone.