There is no Holy Grail
In anything, be it guns, ammo or carry.
I was born in the mid '50's and had some darn interesting Mentors & Elders that had been there and done that, and not just in the USA, also abroad.
Tueller drill: Well the Tueller incident had not yet happened when I was mentored that a perp can reach you in about 1.5 seconds from 7 yard/21 feet.
While we did not do stopwatches that much, we did have "charging targets" that could reach one in 1.5 seconds. We did these drills with handgun, rifle and shotgun by the way.
We also did one-on-one drills and used water pistols when I was younger, and later some other things.
I am 56 years old now, but if memory serves I was about 50 years old the last time I was timed.
Model 1911 from IWB .9 seconds from "beep" to first shot on target.
Model 442 : .7 seconds.
Kel Tec P11 .8 seconds.
Now was mentored it was not cheating if it worked, instead ingenuity. So I have removed a 1911, Model 10, 042, and what not from hip and put into a jacket pocket, or even blazer pocket.
If memory serves I was able to use a 642 and in .5 seconds shoot the threat target from my blue blazer. Yes, I shot thru the pocket.
I think it was around .7 when I did it with a Colt Combat Commander, from a windbreaker pocket.
Oh both of these were done weak handed. Something else I was mentored on as well.