Having only flown limited times in the CT, I am speaking from a position of considerable ingnorance. However, if I am not mistaken, themajor difference between the CT and the Mission Arena is the concept that the Mission Arena will be structured, and not a simple Main Arena with a limited plane set, like the CT appears to be.
So you are restricted as to what you fly, but you will fly in an organzied fashion, with a stated objective and rewarded for a job well done.
TO me, the CT, is only the MA, with a limited planeset,and somewhat better sportsmanship.
I'm very very interested in the Mission arena, and will probably make it my new home.
I have no qualms about giving up my F6F. Flying a limited planeset only helps your dogfighting skills, as you learn the capabilites of the planes you fly against in the Main. It sure can't hurt.