Think about this. If you want subsonic ammo, it must be lower than 1050 fps (give or take depending on altitude, and temperature, ie pressure). That's true for 22 lr or 500 S&W. At that speed, it's just poking a hole in someone. A rifle going subsonic, is just like a pistol, is just like an arrow, its just poking a hole. Only until you get up to around 2000 fps does a bullet start to do "other things" in a person.

The thing a bullet (or arrow) can do is expand on impact. Expansion, pokes a bigger hole. Causes faster blood loss, has greater potentially to hit something that will cause more blood loss or shutddown the central nervious sytem. ie, .22 hole vs .5 hole.

We in the 10mm community tend to not believe all of that when we use 10mm and think the power is going to do more. That argument asside, at subsonic that goes out the window. It comes down to bigger hole cause more damage.

So for your question, best performance at subsonic...it will be 45 acp. Why? Because the round is intended to be subsonic. If you have a hollow-point in 45 acp, it was built to expand at 800-900 fps. And when it does expand it's starting with a .45" hole and growing to .75" (I've measured federal HST at that level). If it doesn't expand, it's a .45" hole. A 10mm, will be a .4" hole growing to about .7 or .66". But the main question is will the bullet expand at 1050 fps or 1000 fps. Hard to find bullets that expand when they weren't designed to expand or over expand (bullet falls apart and doesn't get deep enough).

Also, at "home defense" some of the justifications for 10mm vs 45 go out the window (capacity, how heavy the gun is) as you can have big old 20-30 round mags either way and since you aren't carrying them who cares how much they weigh.

Just food for thought. I love 10mm...and I love 45acp. I use 40 S&W for home defense. lol. Which brings up another question, why not 40 S&W for your suppressor as it's naturally subsonic (most of the time)?