I haven't been really into or messed with gas guns for five or six years, and maybe the technology has overcome it, but to me "piston" and precision don't go together. It's been my experience that my most accurate gas guns are all direct impingement, and that the advantage of piston is ONLY that they don't get as dirty as fast, and you can keep shooting without cleaning for a lot longer before it starts to malfunction. Seems like all the piston guns I've owned and shot were disappointing in precision, where as some of the direct impingement rifles were sub moa consistently. IF you care about such things...