I have the non-Canadian .177 version. After the barrel is cleaned up on both ends, the gun is quite accurate. The trigger group can also be polished, and have the adjustment grub screws replaced with one with a ball bearing at the tip. That improves the trigger quite significantly.
The regulator is adjustable, but not the HST. The hammer spring is *way* too strong for me, so I collapsed a few coils. This has another beneficial side effect, the hammer is now free flying, there is no burp!
With all this done, my little .177 shoots JSB Exact Heavies at 500 FPS. With a 200 bar charge, I can shoot 21 shots (3 mags) with very little AD and ES.
A .22 is probably more efficient, but we are not going to see a huge gain of shot count or muzzle energy, I think.
The PP800R is a great tinkerer platform. However, I do not recommend it as a "shoot as bought" gun. Others may disagree!