Apples to oranges.
This from a guy who was running an RDO on an AR in 1990.
If you need adjustable gas, and most don’t with a properly ported barrel, you likely need a piston gun.
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Seen the data, have the guns, and perceived some differences, but I can't get excited about mid vs carbine gas anymore.
I'm fairly certain that a carbine gas system with a 16" barrel is more about compliance with law rather than optimal weapon function. It's my experience that a 16" barrel runs a touch smoother with mid length gas and won't be as rough on parts. That said, I bought my first AR right when the ban expired in 04. It was a RRA carbine with a 16" barrel. It has since been sold, but even if I still had it, I highly doubt that I would have run enough rounds though it to experience any negative effects of that combination. I'm not even sure there were 16" mid lengths available back then.