How mature are the piston conversions????
Well I have yet to see one knocked up or needing a shave
In all honesty I feel they are a hardware solution for a software problem. The AR platform is reliable if kept lubed and reasonably clean. I have customers that run courses of 5K rounds per weekend with no issue. They maintain their weapon as a normal course of action and have no problems.
I am sure if Eugene Stoner felt the piston system was best for the platform he would have made it a piston actuated action.
They add weight and mechanical complexity.
Complexity of a mechanical device just adds potential for that much more to fail.
Parts left off cost nothing, parts left off cannot fail.
Bolt tilt is caused by recoil impulses being introduced to the bolt carrier in a way it was not designed for.
When a gas impingement system acts upon the bolt carrier the gas impulse exerts pressure equally in all directions. The bolt carrier moves due to this impulse the only direction it can, straight back in a linear fashion.
With the piston system the recoil rod imparts the recoil impulse strictly on the top of the bolt carrier, this adds a rotational force to the bolt carrier. Now you have the bolt carrier wanting to rotate downward as it travels rearward.
The machine isn't designed for such.
So in essence you have attempted to fix a relatively infrequent problem but have added another problem that occurs on every round fired.
Nothing like taking a step backwards.
If you want a piston rifle then get one that was designed that way from the git go, such as a Sig or AK.