I see a lot of arguments against purchasing deeply discounted older generation iPads in the name of future proofing. Personally, with how fast technology moves, I don't think there's such a thing as future proofing. I just upgrade when there are new features I find useful at a price point I'm willing to pay. So now this made me curious, do people actually keep their iPads long enough to lend credence to the future proofing argument? How long have you guys had your iPads?