SPONSONS

Okay, after over 15 years of kayaking I STILL don't have a bombproof roll. I am determined (seriously thinking about it) to master this skill (okay, get a few good YIPPEES in there) if only to avoid a time-consuming and chilly self or assisted rescue. Oh, and it would be nice to have the confidence to go on "advanced" excursions without being a risk to myself or a nuisance to others.

In the mean time, and even IF I get the roll down, I am curious about SPONSONS. I am wondering why they are not part of what we consider rescue arsenal for the fatigued, dizzy or sick paddling partner particularly when waves increase the risk of capsize (singular and plural) during a tow.

I have only found Harmony brand sponsons online. Are there others?

Are there sponsons that can be attached to the kayak that WON'T add drag when not inflated?

Are there sponsons that can be inflated via a CO2 cartridge instead of puffs of air?

Are you familiar with homemade sponsons that work as well or better than Harmony?