But it sure does make a 5" 1911 balance well. Same thing with a 15-rd mag in a 4" XD45 - great balance.
It's not about looks, and it's not the mag of choice to try to conceal, but you need to have one on you when you carry - if you end up having to use any ammo whilst carrying, you'll wish you had one of those on the first reload.
When I carry the 4" or 5" Kimber, they have a CMC 8-rounder in them and one in the chamber. I have two CMC Power 10s with me.
When I carry the XD45 (that's the daily pistol now), it's got the 13-rounder, one in the chamber, and two 15-rounders as spares.
I have no idea how many 1911 mags I have, so I think that's something I need to count, now. I'll tackle that job in the next couple days. Most are CMCs, a few are Kimber mags, and a few more than a few are Wilson Combat mags. I'll figure it out.
Mike is right again, too - Mec-Gar makes some great double-stack mags. I've never tried their single-stack mags, but have some of the doubles. Those were OEM for the Kimber BP Ten II, Para 45, and a few other manufacturers.