you wouldn't need subs for the p22. normal .22 ammo out of anything 4'' or shorter is almost always coming out subsonic.Took me 100's of rds to break the habit of letting my left thumb ride to high but fortunately I had a weapons instructor that screamed at me all day until I finally got it through my scull to just use that left paw as a cup. As far as Walther Corp i'm not very impressed. I bought a .22 suppressor and was excited to use it on a P22 I had, then I read a review that said it wouldnt cycle subsonic rds! Why thread it then? So I found out all the newer PPK's in .22 are threaded and I said to myself: "self, what would look cooler than a PPK with a can on it?" Well I bought a brand new one and guess what? The damn dbl action trigger pull is SEVENTEEN POUNDS!!! I wrote to Walther and asked them if a gunsmith could in anyway improve that for me since it would be hard to hit THE WALL at 17lbs, that is if the trigger or my finger didn't just BREAK OFF. I guess they were hard pressed for time that day since the letter I got back from them just said "no". So to sum up, don't buy ANY Walther .22 if you want to use your suppressor or if you value your finger. A HiPoint doorstop/paperweight is much cheaper.
1080 fps is the sound barrier, typically any standard .22lr is faster than that, thats why you see a lot of subsonic .22 ammo and little or no in .45acp...you wouldn't need subs for the p22. normal .22 ammo out of anything 4'' or shorter is almost always coming out subsonic.