Piston systems are designed to relieve you of the weight of your money by converting to weight on the end of your barrel.
Yes, they are cleaner. But they can also damage the AR, because the carrier tilts when pushed by a piston, and it can wear through the buffer tube extremely quickly.
I'd go with just a chrome bolt and carrier. Same reliability, and easy to clean because you only need to wipe it down to clean off the carbon fouling.
