I am perfectly happy with only two 10rd mags for the range, and at my local competitions, courses rarely require more than ~18 rounds at a time. And if I ever need one, there are always other Glock shooters who would let me use a spare. I don't forsee myself carrying with a larger mag in the gun and I can't say I'd be any more likely to carry the larger mag as a spare over the extra 10-rounder. My gut tells me to just get as proficient as I can with the 10rd mags, and maybe get in the habit of always carrying the spare in some capacity (even if just in my backpack or whatever). This is largely because I like practicing how I will carry, and I know 90% of the time the weapon would have the 10rd mag loaded. The only real time it would see use would be for the occasional competition with a longer course of fire, or if a gang of zombies ambush my house. Otherwise I don't feel particularly undergunned with 11 rounds versus 18 (even when I daily carried a 17L, I often seriously considered chopping the grip for G26 mags). What do you G26ers (and G27 / G33ers) think of just sticking with the two factory mags? Thanks.