I have shot my OSS DS more than five hundred times with all kinds of ammo and it works every time. They come with two 12 rd mags and have the double/single operating system, with a decocking mechanism which allows you to leave a round up the pipe and twelve in each mag.
I just ordered two more mags because I want to break in alternate mag springs and be prepared. With Golden Sabre rounds, that weapon is a perp stopper. But always think of your pistols, whatever kind you trust, as merely the means to get to a real weapon, a 12 gage in pump with a bandoleer of extra rounds, in #2, 00 Buck, and slugs.
And while planing where to place pistols for quick access, do not discount the venerable 1911. There are ten round mags, eight round mags, and you can purchase a well made Phillipine version for around $375. Well made Pistols sold under the Rock Island name brand.
45 ACP ball ammo can be purchased at Wally World for around sixteen per fifty, and in 100 round loose bags at gunshows for around fourteen per fifty. The 1911 setup is recoil friendly, but my Taurus OSS DS is the finer of the 45ACP I trust. It's a 5 inch barrel big frame but a very comfortable grip even for women's hands. You won't even be tempted to conceal carry with it, unless you'll wear a fanny/belly pack or a courier's pouch.
Last but certainly not least, my perferred CC pistol is the very reliable sweet shootin' CZ82, and I keep it in the van with two or more extra mags, Hornady hollow points in all.
Oops, meant to ping this above to you.