I bought a Spare Air 3.0 I have since found out that most dive shops don't
care for them at all but I have had good luck while testing mine. I was
able to do the following;

19 breaths at 35-40 feet, and these were deep, solid breaths.

Completed nearly all of my 3 min 15' safety stop on one.

I think those are pretty significant numbers, I sort of relate it to
carrying a pistol while hiking (Or pretty much anywhere really.). You hope
you never have to use it but you feel better knowing it's there and feel a
little more vulnerable when it's not. I am definitely pleased with this
purchase. It's not big and bulky like a typical Pony tank and small enough
to still be efficient carry for a recreational diver. I know it will never
replace a real Pony tank for people who need them but for me it filled the
bill perfectly and that is mainly for security and peace of mind.

--
Bart A Lane
bartlane@e/a/r/t/h/l/i/n/k.net
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