Well, I ended up inflating my HitAir YS vest this morning. Practicing this concept of bump starting while trying to waddle the bike fast enough on the flat road, letting out the clutch in second gear poised to pull the clutch back in if it doesn't start, and relaxing a moment too soon when it seemed to start then changed it's mind, means coming to a very quick stop. "There was nothing I could do, I had to lay 'er down."
But let's not dwell on such trivial details, shall we? No pictures = never happened...
It inflated very quickly. I landed on my shoulder so the vest didn't cushion the main part of this particular type of fall. But it puffed up in front and back. It stayed inflated for longer than I can imagine anyone would need it for protection. It was a little hard to wiggle out of so I could turn off the fuel petcock. I wear the vest over an Olympia Motosports Air Glide 3 Mesh Tech jacket that has armor in it.
Deflating the air chambers and snapping it back together took only a minute to do, very easy. There's a video http://www.safermoto.com/media/reassembly.html
with peppy music showing how to put things back to usefulness. It's almost as easy as falling off a motorcycle. *ahem*
Moving on, another concern I've seen people asking about is having a metal canister going across the ribs. When changing the co2 canister, I noticed there is a flat rigid protector area behind the cartridge which would likely spread out any force the canister might put on your ribs. But the front also inflated a lot and it seems unlikely that a force would be strong enough to get through the air bag and past the shield to make much of a difference between having the canister there or somewhere else. Not tested science though, just an observation.
Only one question remains, what to do with the used canister? I emailed our trash and recycling company to find out.
Just ordered two additional cartridges, and a buckle connector holder for when I forget to drape the detached tether across the seat and it dangles by the hot exhaust pipes! Too bad there isn't airbag pants or sleeves.