In MT we tried to pass a bill making it legal to big game hunt with them and it failed

I was all for it, as I have bad ears and would LOVE to have one to use. With a big bore, they still put out enough noise to be bothersome, but not so much as to be painful...
I've shot them on a couple AR's with normal ammo and subsonic. The subsonic is Sweet, but of course, it really affects your long range stuff. My short term goal is to have a nice AR with one... unreal for Prairie dogs...dogs never go down if they are out a couple hundred yards or more.
Used one on a 243 and it was sweet as well. Did not affect accurracy of either AR's or the 243, with the ammo we were using.
My buddy has a Walther P22 with one. That is SWEET! Almost no sound and with subsonic, you only hear the action cycling.
I think for around $600 total you can get your permit, get a decent suppressor and have your barrel threaded.