Things I liked: Reliable and does not have spring fatigue.
Things I would have changed: Can't think of anything.
What others should know: My piston actually had some problems and jammed up after about 200 shots. Pyramid air replaced it for free after i sent it in and it works great. Probably just an unlucky piston conversion. There is still some recoil even after this conversion piston is added to your rifle, so i recommend getting a scope stop.