I use full size in the house, half size in the truck. I prefer metal, but they rattle just a little bit.
Discussion
I've been looking for something with a larger capacity. my savage apex .350 is a solid hunting rifle, but the mags only hold 5 shells. great with deer, hogs, coyotes, but not great for defense.
It's standard AR mags, so you can fit it with a drum or 2x drum (100 rounds) if you like.