Just the one in my Sig.
I also don't carry a flashlight, medical kit, or tools. I have those items available in my vehicle and in my home. I don't schlep that stuff around on an 8 Pound Batman Belt.
After years of nearly-daily watching CCTV / Security Camera footage of self-defense shootings it's readily apparent that mag-changes in a fight are incredibly rare.
Now what is NOT rare is semi-auto malfunctions. Those happen a lot. How many are magazine-related? No way to know. So if someone carries one spare to address potential mag failures that makes some sense.
But carrying multiple magazines for extended gunfights? Nope. There are, for the most part, no incidents of that nature. I've seen gang-on-gang or Police battles where a lot of rounds were fired. But crook(s) Vs Civilian fights are not like that. If shots are fired it's few, and quick. This is prevalent to the point of making lugging around multiple mags about as necessary as carrying a spare alternator in your car "just in case"
That's my observation-based opinion on this. But if other guys want to roll heavy, fine. Chiropractic care is readily available.
