With SPGs, no matter how many tanks I'm carrying, I can tell the pressure in any individual tank by looking at the SPG attached. Reasonably foolproof, even for a reasonably talented fool like myself. For the sake of argument, if I want to know the remaining pressure of the gas I'm actually breathing and I've managed to get confused about which tank it is - please remember, this is for the sake of argument, there are so many ways I'm not breathing from a tank without knowing exactly which tank it is, try not to get distracted and start flaming me - I can trace the second-stage hose to the tank and look at the attached SPG. Still foolproof.
With a ten-transmitter AI set-up, how do I know which tank goes with which read-out on my computer? I ask in all seriousness, since I've never used a computer that could track more than one transmitter. Do you have to number the tanks, or assign each gas a transmitter code before diving, or what? In the event of a gas-management problem, is the AI computer going to add stress because you can't do something as simple as look at the SPG attached to a tank?
Maybe I'm just stupid, but I forget to tell multi-gas computers that I've made a gas switch. I've fixed that problem - I've gone back to diving runtime with bottom timers. Can't see myself swapping SPGs for AI any time soon. Oh, and the AI computer I did own? It's a paperweight. endless synching problems, two transmitter failures, followed by a catastrophic failure of the computer itself. I could have bought so much more interesting kit for the price of that computer...
As for the data-gathering argument, if I want to know how much gas I consume during the bottom phase of a dive, I look at my SPG when I get to the bottom, keep track of average depth, and look at my SPG before beginning my ascent. I use a pencil to write it all in my wet notes, which have yet to flood/crash/spazz out for no apparent reason. Call me a Luddite.
