The issue to me is being able to draw and defuse the situation without going into a panic, and blasting away. I know you were probably taught not to draw unless you are going to shoot, I think my way is better. I don’t want to shoot anyone, but don’t want to be shot myself. Why let things go too far, when there is a chance to stop, before someone gets hurt?
I’ve spent large chunks of my life in harms way, not going to argue about how I lived through it. Most of the time I didn’t have an instruction book.
While I believe it's probably not wise in many areas to pull a gun as you did in that situation, you knew the circumstance far better than any of us who may critique your action. As I commented, if there is a strong probability that you are in a life or death situation it's much better to remain alive and be judged by a jury of your peers than to be dead and carried by your six best friends.
Around this area, small town north GA, it would be hard to find 12 jurors who would convict an honest man for defending himself or others with deadly force against an armed and threatening POS who he has good reason to he believe intends to rob and/or kill him. A man accused of that in a court might just end up being awarded a medal by the jury.