It turns out the OSP (and supplied ammunition) is a hoot to shoot.
Now my question is the unmodified factory grips seem to have a very strange shape compared to other great (Morini Free Pistol), good (Rink Air Pistol/Free Pistol/Sport Pistol) and poor (Steyr Air Pistol/FWB Sport Pistol) grips. The front of the grips are large and awkward, and the rear is narrow. The previous owner had a Free Pistol with a Morini grip that fits my hand splendidly, so I guess my hand is close to his hand in dimensions.
Any insight on why the OSP grip seems to have a weird shape compared to my other grips?
An example of the OSP model I have (image from another forum):