There is nothing as sweet as a comeback, when you are down and out, about to lose, and out of time.
I think that age as a number is not nearly as important as health. You can be in poor health and be pretty miserable at 40 or 50. If you're in good health, you can enjoy things into your 80s.
Warren Buffet told me once and he said always follow your gut. When you have that gut feeling, you have to go with don't go back on it.