The nice thing about the Air Force platform is that you have a myriad of options. I have a .22 Talon with the 18 inch barrel and also have a .22 Condor with the 24 inch barrel. You can literally swap barrels back and forth, you can even swap tanks and put a standard tank on a Condor or visa versa.
There shouldn't be any problem switching back and forth between a .22 and .25 barrel, I'm just not sure if you'd need a heavier hammer weight for the 25,,, but even if you did swapping them out is no big deal.
Harry has a 25 Condor,,, he could probably answer your question in more detail.
As for the Groundhog shots,,,,, if you were shooting a .22 Condor with either the Kodiaks or Eunjins I think you'd be able to whomp those groundhogs pretty well at longer ranges.
I love groundhog hunting and spend most of the summer hunting them at the duck farm I pest hunt at. My springers and my 18" Talon .22 work very well but I wound up getting the .22 Condor specifically for long range groundhog hunting. BTW.... I took quite a few G-hogs out to 40 yards with my Talon firing CPH's in the 900 FPS range with no problem.
Jeff