I carry both. Sometimes one or the other. Sometimes two of one type. Sometimes one of each. Sometimes, even, I'll carry two of one type and one of the other.
Then, there are the rare days when I'll carry two autos and two revolvers.
Normally, a full sized auto + a compact or subcompact auto + a Charter Bulldog 44 (or a K frame sized .38 or .357) + a J frame .38 or .32.
The fastest reload is to draw and fire another gun. The good ole Jim Cirillo/New York reload.
Having a backup to your backup is good insurance in an unsafe world.
One is none. Two is one. Three is two. Four is three, ya see?
Just like, sometimes I drive a car/truck and sometimes I ride a motorcycle. (I always wear safety gear when riding)
And, sometimes I do both.
It just depends. How bad of a neighborhood am I being required to go to?
Am I wearing my level IIIA vest under my shirt?
What time of day or night am I required to go?

Bear in mind, I've spent my entire life avoiding bad areas/situations. It works most of the time.

About being old, I'm 46. Not young. Not old.
But, that's all relative.

I'm old enough to not look for trouble.
I'm old enough to realize I'm not immortal.
I'm old enough to know just how fragile my human body and life can be.
Still young enough to ride and to shoot my favorite guns.

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What would Jim Cirillo do?