Pneumags are more complex to build, and they do have more possible failure points, but that being said, I don't think they're any less reliable than a standard Automag (if they're built properly). I've had one for almost ten years now, and the pneumatic components haven't failed yet. They get sticky every few years, so I have to take everything apart and oil it, but I don't think that's unusual. They do require slightly more air, though, so if you can't refill your tank in between games, that's probably not the way to go.
But yeah, for someone just coming back into the game, I would stick with an x-valve and RT on/off. No need to make things more complicated than they are. (But if you change your mind, I know someone with a pneumag for sale.
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