As I am sure that you are aware, only the Swift is a factory round, but the other two are fairly easy to make from .243 Winchester or full length BR brass if you want to use a small primer pocket.
And as much a hotrod as the .220 Swift is both the 22/243 amd the Cheetah are faster yet, but at quite the expense of barrel life. The Swift is overbore as it is and coming up with something else that burns another 20% more powder for a 5% speed gain is rather whoopdedo to me.
I think that is one reason the .223 Win short mag fell on its face was that it was a lot of boom and expense for not much gain. Unless you are counting how fast it can toast a barrel that is.
If I had a lot of money (I don't) and the desire (I don't) I might want a real screamer like the Cheeta but since 90% of the time I don't even shoot my own .220 Swift full throttle anymore, I have to wonder why anyone would want to go to the bother? And any furry animal that you shoot with one of the three certainly is not going to tell what you killed him with.