No mate neither the 200s or 400s are regulated.
Regulators give you a measured volume of air each shot regardless of the air pressure in the cylinder. Well to a degree anyway. They give you more shots per volume of air stored than an un-regulated rifle, and are believed to be more consistant, in that the same amount of air is released each shot.Less chasing the zero up and down as the cylider empties

Cons, well thay can go wrong. They; If fitted inside the cylinder, take up room, so you can end up with no more shots per charge from a modified rifle where a regulator has been retro fitted.

Hope this helps a bit.