Since I've made the Agent comparison before I thought I'd chime in.
I agree, the Second Dimension is smoother than the Agent. The pearl reactor cover stock skids through the heads easier than Pearl R2X ETM and the response in dry is more violent. But when you factor in the higher RG in the 2nd core the breakpoint seems to be the same and the overall ball motion is real similar.
IMO if you liked the Agent you will love the 2nd. Similar ball motion, usable in the same condition (second ball out of your bag in a broken down heavier shot), and backend continuation that drives through the pin deck better than the Agent. All of these characteristics make the 2nd more reliable / predictable.