I picked this one up for $90 a few years ago. First issue was leaking back thru threads of the 88 gram cylinder. So I took emery cloth to the threads as they were not a good fit to the gun, plus wrapped threads with plumbers tape...solved that problem...by the way,the tube under the barrel does nothing...(that is a throw back to the Crosman pump guns)
It has low power and high power setting, depending on how far you cock the bolt. High power at 80 degrees ambient was about 600 FPS on my chrono. Accuracy was good using JSB;s (see pic below).
(I might mention that the 88 gram thread fit on my CO2 850 was same issue, but I converted that rifle to accept 9OZ paint ball tanks...
I have taken some squirrels out to about 30 yards.. the scope is a Walther 6x42...very sharp, clear.
Six shots under a dime at 25 yards..
My scissor jack bench rest setup.... lol ...!!