Years ago I shot two "high power" piston guns, a .25 cal Beeman Kodiac springer and a .20 cal Beeman Crow Magnum rammer.
The Kodiac was shooting 29 grain domes at 30fpe and I had no issues with cocking and shooting and the shot cycle & accuracy was acceptable, however the size and weight was "non-starter" for me.
A few months later a fellow brought his .20 cal Crow Magnum to a field target match (not yo shoot the targets) so I could check it out claiming he got 3/4" ctc grouping at 50 yards with it. I really didn't get a chance to check the accuracy of the CM because the cocking effort of that gas ram was a GUT BUSTER for me and I only shot it 3 times. The shot cycle was exceptionally sharp which I'm sure would be a "scope buster" (I'm pretty sure the Kodiac would also be scope wrecking) and the trigger was "terrible" compared to my Rekord triggered R9. After the "trial" I decided that if I were given a Crow Magnum for free I'd simply sell it.