yep - a dedicated .22 upper is preferable. Even better is a SBR dedicated upper with a can!
I think a .22 division for all types of matches is a great idea. It would help grow the sport, be a great division for kids to start in, and even allow some guys to shoot who cannot afford the increasing cost of center fire ammo.
It works in the steel matches.
There was a thread on that topic a year or so ago. I was surprised at how many people were against a .22 division. Some smart a**es rebutted with: "what's next, an airsoft division." If you don't like it, then don't shoot it