"For impromptu gunfight, pretty much WHOEVER SHOOTS FIRST WINS."
Having never been in one, I'm not the resident expert (and I hope it remains that way).
That said, from a lot of reading, watching YouTube vids, and so on, my impression is that whoever shoots first may not necessarily shoot well.... and so, perhaps, "whoever shoots best (providing he is not incapacitated immediately) stands a good chance" of winning.
Lot of variables, there, I know.
But for most of us, we are not going to shoot first. We are going to react, and hopefully survive the initial outbreak of hostilities, and play catch-up from there. That is the way it goes. We are not the aggressor, and will very likely be the last one to know that a gunfight is going on.
Unfortunate, but it's part of the deal. We are going to be behind the 8-ball from the beginning. That is why we need to be twice as calm, twice as accurate, and (probably) twice as lucky.
Sucks, but the alternative is going unarmed, giving up and leaving your fate to the ruthless.
No thanks.