The grip screws have been a bit of weakness in the Pup for some people,stripping heads have been a complaint for a long time.
Indeed it has been. That's one reason why I ordered and tried the black screws from Rohrbaugh - to see if I thought they might be a better screw to use and less likely to strip the heads.
It's my opinion that they are better than the silver screws in this regard simply because of the material choice. Stainless has advantages as a screw material because it won't rust and in that sense is a good choice for a grip screw in an all stainless gun. But as a fastener material it's pretty bad - most notably in that it has a high rate of creep - tighten a stainless screw and it will elongate over time and get loose. Stainless screws may also be a little on the soft side as well which makes them easy to strip the hex socket.
While I was told that the only difference between the stainless and the black screws was the color, when I got them I tested them with a magnet and found that the silver screws are non-magnetic (as most stainless alloys are) but the black screws - like the ones for the VZ Grips - are magnetic which means they're not stainless but likely some steel alloy. They also seem to be quite a bit harder than the silver screws, and the fit of a hex key is much tighter than the fit on the silver screws.
I believe that the VZ Grip screws would address the grip screw problem on the R9 because they are also magnetic alloy steel. I also believe that the black screws from Rohrbaugh would address the problem as well for the same reason - a tougher material.
