I know this is an old old thread - but I'd like to see the R9 chambered for .22
A lot of good training can be accomplished on a .22 version, training that carries over to the R9.
Just like some training can be done with SnapCaps, there is a limit to how much can be accomplished. Some training has to be done on your primary carry weapon, the R9 itself - that'a a given. But having a .22 would allow an R9 owner to do more live fire training more cheaply and also save wear & tear on his or her carry R9.