I'm lovin' the 50 at the top. It just needs to have the knife repositioned higher in the stack to take advantage of weight on a downstroke. The rest of them would take an octopus to operate.
About 10 years ago there was an episode of cops where they showed up at a shooting. The guy who got shot was a 300# gangbanger. He lifted up his shirt 2 show the gunshot and all he had was a nasty bruise. didn't even break the skin. he was laughing, telling the cops he'd been shot a few times already and he certainly wasn't worried about a 22.
I'm with you on the .22 being best all around. Also, if it came down to bartering, nothing better than .22 rifle and shells. They would be invaluable. Everyone should have several.