[cudabob496]

For the original question, if you end up in a roll keep the arms close, tucked into the chest, hands under the chin. Be a pencil. Enjoy the earth-sky-earth-sky experience. Otherwise you're flailing and whipping your limbs into the floor or worse and breaking bits.
I've never considered an air bag vest for street riding, it seems to me like overkill unless I was riding crazy, in which case it's time to slow down. That's what track days are for
That said, if I lived somewhere cold I'd probably consider one for spirited rides, I mean, if there's no downside I guess why not. It's just too hot here to wrap up in even more crap.

And of course, there's always the possibility of some grandma rear-ending you at 25 mph at a stop light.

 

[Zaph]

Low sides are far superior to high sides. Example: 140 mph high side, I broke 9 bones and was severely disabled for months. Several low sides, including one that was 130 mph I never broke more than one bone or a minor sprain.

A highly skilled rider can turn a high side into a low side. Observe this MotoGP crash pic from many years ago. His bike is high siding but he scoots off and comfortably slides on his butt and back to safety.

Ever notice a highly skilled rider begin to lose traction in both tires in a turn? The first thing they do is lift their foot off the outside peg. The is the first step in the maneuver to preventing your body from getting launched into space in a high side. Sometimes this step allows a bit of decrease in lean angle, which allows the tires to regain traction, and it's possible to get control back.

It's really cool if you can stay clam and loose enough to make this happen, but most people, even racers are going to tense up, pucker their sphincters and target fixate.

 

[Zed]

And of course, there's always the possibility of some grandma rear-ending you at 25 mph at a stop light.

True enough. Most of the time I'm in between the lanes at lights but of course things like that can just happen. In my mind at least though, it's quite rare an accident was unable to be avoided by better actions from the rider beforehand. Honestly if I was that anxious about something happening I think I'd find another hobby. Most of the time I'm in riding jeans, decent boots, gloves and a mesh jacket. Cooler weather I'm in leathers, unless I'm wanting to be off the bike at a destination. I really feel that's all enough for the road. I had one crash on the road it was a high side and I superman'd onto my belly, in leathers. Wasn't too fast so I was just sore, but that was on a V2 Tuono, with a frozen back tire I didn't contemplate as my bike was normally inside and I live somewhere generally warm. I have some more maturity now and only ride at say 70% on the roads, especially cornering wise. I think that's the main factor for accident avoidance if you do everything else well. And that's why I went to a Ninja, enjoyable to ride without overdoing it