I remember paying $85 for a used 15 round USP magazine. I'm happy to pay MSRP for Glock OEM mags. I prefer to use brass case instead of steel case, but I want the option to be able to use steel case. Having paid stupid prices for quality mags during the dark AWB years, I value the mag quality way above the mag price.
I'm a magazine snob, and I'm not even sorry about it. If I wander into a gun shop just to look around and want to be a good customer, I just buy one or two OEM Glock mags and toss them into one of the mag caddies once I get home.
I would make an execption to the Magpuls if I was forced to use 10 round mags, but that hasn't come up as an issue yet.