I have a Chaser in .22, great rifle. Whisper quiet with the long barrel & 'suppressor', excellent trigger right out of the box and adjustable, not picky with types of pellets. Super accurate. Long run time on one CO2 cylinder and super easy to replace. I think the optic rails on the reciever are 11mm not dovetail. Also runs the Stormrider magazines, not sure why that's not mentioned in the owner's manual. I run a pretty chunky 30mm red dot and had enough room to mount it and clear the magazines, but if you prefer a scope it's either the single shot tray or a very high scope mount.
Well made and a great value, I don't know of a better quality CO2 rifle.
I love my old vintage Benjamins & Crosmans but the Diana Chaser gets used the most.