I don't talk about it because I would never have the courage to do it. Yes, it's 100% fail safe and relatively fast/instant from at least 200 feet onto hard surface. Water is iffy, especially seeing some of those extreme dives. It's too dramatic and messy either way. Just like guns. 100% fail safe with a hollow-point 9mm or bigger in the mouth pointed slightly upward. I have guns in my house. But I can't do it.
SCUBA and inert gas, my method, is painless, peaceful and relatively fast. I'll have two or three breaths to think about it. But I'll be lying down, relaxing in my bed, instead of free falling and screaming, or blowing brains out through the top of my head. But if you have the guts and are landing on hard surface from at least 200 feet, I guess the last few seconds of your life will be a thrill.