I might mention one thing that happened with Kel-Tec. For a long time, it was considered appropriate to perform the "Fluff N Buff" procedure to ensure that all would be well. It was a very common practice for the P3AT. Very common!
Then, I eventually read that Kel-Tec no longer approved of user changes of that nature.
I would not modify the feed ramp of my R9S thinking that Rohrbaugh might feel the same way. This is only mentioned in case someone is tempted and had not thought of possible consequences.
Meanwhile, I do not mean to suggest that there are feed problems with the R9, except possibly a few isolated incidents.
Bill