When my life depended on it I chose inertia after a pump. 870, M1-Super-90, and a M-2.
In the blind it's been a combination of both. 870, 1100, SP-10, A390, Pintail, M2, SBE, SBE2, and A400.
To say that gas systems have become more reliable is an understatement. Just look at the recent USMC contract for the Benelli M-4.
But it all boils down to how well you maintain either system. I've been a Remington armorer since '89, Benelli/Beretta since '91. Almost every malfunction I've ever repaired (90%) has been due to LOM or outright negligence. Just because it has synthetic stocks and a non-blued finish doesn't mean it doesn't need a little TLC.
Pain or damage don't end the world. Or despair or f-ing beatings. The world ends when you're dead. Until then, you got more punishment in store. Stand it like a man... and give some back.- Al Swearengen