Good for you. You're a good shot. The OP might not be, hence the need for something more powerful than an air rifle.The fact that I can outshoot both my parents, both of whom have been shooting their entire life, and I still average higher than a lot of people who have been shooting their whole life. I've placed 1st in the state of Michigan multiple times at state level competitions and have been to nationals a few times as well. With the exception of a few very good shooters, I am a better shot than most people in my club, which has placed top in the state multiple times as well[...]
Personally, I would never attempt a one-shot kill on a larger pest with anything less than my .45 lever action. I've seen possums take three 9mm rounds at point blank and keep kicking. I've seen .22LRs bounce off a rabbit's head at 10 yards. Just the other day - I posted about this - we had a field rat and The Man hit it with 5 .22mag rounds out of his North American at less than 4 feet. It was still trying to get away (and doing an admirable job).
If I'm going to attempt a one-shot, I'm going to use the round that will leave the least amount of pest remaining in one piece.