I wonder myself, but so far the three older ones I own have been fine -
A Crosman Blaze from 2015
A Hatsan Edge from about the same time
An RWS 350 from 2016
I hear that some of the gas springs are rebuildable (just O rings and silicone oil). If they are physically worn or aren't rebuildable they can be replaced easy enough.
One thing that I really like is that they dont have the spring torque/twisting motion of a coil spring and the rifle doesnt roll in your hand during the firing cycle. Not really an issue with lightly sprung guns, but the magnum guns are another story.
That Hatsan is not a finely made rifle, but it makes large power from a medium package and groups well for small money. And thats why I like it.
