Dregsfan, what size do you use and recommend for the AI?
Do do you inflate those before leaving shore? I assume you would.
Like the proverbial PFD which is never worn, airbags would only truly be effective if checked for leaks and inflated in-place prior to launch. They have a great chance of working then.
If you haven't done this, can you imagine bobbing in swells, moving gear around, positioning the floats and blowing them up when the bow 1/2 full of water? How long would you need to straddle the hull, blowing with the front or rear hatches wide open?
You might also need to blow hard enough and fast enough to displace 100+ lbs of H2O. That's a great physical stress.
I would love to see a large self-inflating model that you could use at sea, but floats are expensive enough as is.
As you can tell, I'm more a fan of passive floatation devices. As Cpt-Max says, pool noodles are effective (and a bit more practical than pong-pong balls).
A couple noodle layers can be bent neatly into the bow/stern. Pieces can be cut/taped together to form a custom hull liner that helps keep your other gear stowed dry and tight (a nice way to store your anchor). They even come in matching Hobie colors. Yes, pink
If you have spare PDF's at home, throw them in the hull on every trip. They stuff nicely into any cranny and could save the day - or someone else's life. Guaranteed to work and costs you nothing.
As Plastiki proves, sealed empty plastic containers like gallon- sized milk/water jugs will add float to your boat. Those w/ handles can double as floats for your snorkel gear, anchor lines and such. Cut them a bit and they make great bailing devices. (As you can tell, I'm thrifty too).
I guess it's time for someone to mention hand pumps and bilge pumps now?