Was diving with an old Oceanic Worldwide VT3, with A.I. Wanted an Atomic Aquatics Cobalt (also A.I.). Took the SDI Solo Diver course; 2 computers recommended. Dove with both. The Cobalt basically died on the last dive of a Caymans live-aboard trip; Atomic Aquatics gave me a Cobalt 2 refurb. at no charge (go, A.A.!). So I do wrist 'puck' and console, and may prefer either depending on what I'm doing.
On my 3rd from last dive in Cozumel in September, got a bizarro reading the Cobalt 2; from my log entry:
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Don’t know what went wrong with the Cobalt 2 computer; it listed max. depth 2101 and average depth 44 feet. MacDive, with Cobalt2 downloaded data, listed max. depth 2105.98 and average depth 43.21 feet. I’ve never even been 140 feet deep salt water! The Oceanic VT 3 gave max. depth 59.81 and average depth 44.40 feet. So I’m changing the max. depth in MacDive for this dive to 59.81 feet.
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But on my Caymans live-aboard trip, dive 21 of 25, the VT3 gave me a badly off reading; starting PSI 10, ending 0 (neither was true). But had I not had the VT3 logging my dives, I would've lost all 25 dive's worth of log data when the Cobalt crapped out.
So I dive 2 A.I. computers, both of which on separate single occasions gave me a way off data reading in the log, then went back to apparently working normally, and one died (likely a pressure-related failure) which would've cost me my computer log of all 25 dives that trip...if I hadn't had a backup.
Richard.