FX barrel interchangeability

I am so glad manufacturers are starting to make rifles with caliber swap options. I have an older rifle that can change barrels in a literal 20 seconds. What I like about it the most, is it allows me to use different brands of barrels as well. It's currently sporting a .20 Career barrel from1997. Crosman Preimer pellets at 980 fps sooo accurately at that high speed.