Cons:
With center sheeting I was always grabbing the blocks wondering why the main would not uncleat during tacks. Then once I got used to it, I was always trying to uncleat some odd piece of line in the middle of the tramp on rear sheeting boats.

Pros:
Your crew doesn't saw your leg in half going upwind on single trap Tornado's
It is a lot easier to rig a cascading mainsheet system