I sent my PC 41 to Accurate Ordnance to have the barrel threaded a few weeks ago. I got it back yesterday.
It’s a difficult barrel to thread as the entire unit is squared off and simply machining the end down to threads would look terrible. They bore the end of the barrel and turn threads inside for an adapter.
No metal came off the outside of the barrel. They bore approximately 1/2" deep into the barrel and cut internal threads for the adapter to screw into. There’s plenty of metal left around the adapter for support. There would be even more on the standard barrel model.
Went and played with one of the cans today. Unfortunately nothing concrete, however I could not detect any POI shift at all from unsuppressed to suppressed.