I see no reason to lug around a heavy gun that is designed to hold 15/17/18 and feed it 10 round mags. The thought of it irritates me. It's like putting a V6 in a car that offers a Hemi. I get you gotta do what you gotta do, but having thought of this non-political hypothetical myself, I have elected to carry a full size 1911 on those rare times that I dont go with a pocket gun.
The thought of it is sickening.
I've got a Glock 32 that came with two 10 round mags during the stupid pointless 94-2004 AWB.
Also have a Glock 35 that I bought off GB which was CA compliant and came with 10 round mags.
There is no way I'd carry either of those pistols with a 10 round mag.
Glock 26/27/33/29SF/30SF or a 1911 in 9mm, 10mm, 45 acp - plenty of options originally designed for 10 rounds or less.
A 1911 conceals easily IWB, mercifully pictured with a t-shirt, just add cover shirt (in warm weather I wear an a-frame / thin tank under a cover shirt).