Never too late to enjoy these fabulous airguns .
I have the Mod 220 which uses a similar pneumatic recoil absorber rather than the hydraulic one like yours.
I like the way it is built with the precision and close tolerances of a 10m target rifle yet it looks quite like an ordinary rifle from the outside. The recoil is more like a brief shudder felt after the shot has gone. Love the palm swell and thumb rest too.
Agree 100% with blocking the cocking arm with the elbow when inserting the pellet in the barrel.
Edit: Good video. I have various models of the Giss Dianas that I have set up and my favourite test is to stack 4 flat head pellets on top of each other on the round part of the cylinder and shoot the gun.....they just tremble a bit and stay stacked. Can email you the video I just did if you are interested to see it and have the patience to watch 4 pellets (eventually) being stacked on top of each other.
Those old Dianas are so addictive to shoot