Have to agree with this - I have an Air 1 at home and a work issue iPad 4 which I switch between every day, and the difference between those is immense - the Air is a lightweight tablet, while the 4 feels like an actual stone tablet which might have a few commandments on the other side - properly huge.
The Air 2 is a little thinner and a little lighter. That it does that while having the extra horsepower is impressive, but doesn't change the fact that the original Air is also plenty thin and light.
That's the thing that I find the "argumentative" Air 2 owners don't grasp, the fact that RIGHT NOW there is very little between the Air 1 and Air 2 in terms of performance.
Run any of the top games, the graphically demanding ones, and they run identical on both tablets. The only area I notice a slight difference is in the iOS 8 UI which is a little more "stuttery" in places. I had my iOS 8.1 iPad Air replaced with one on iOS 7.1.2 so I've got the UI smoothness back but I lose out on Metal on iOS 8, although aside from Asphalt 8 and some rain/flame effects there's not much utilising that feature just now.
No one is denying the iPad Air 2 is a beast, but right now it's not going to stretch it legs while there's a large install base of A7 devices and a full line up of A7 devices still being sold and selling well. Developers won't specifically target just the A8X chip because it's too small an install base, the money isn't there right now, but it will be in 6-12 months time.
And when iPad Air 3 comes out and all those with iPad Air 2's who said they "keep this one for a while" upgrade, they'll be the ones telling us that the Air 3 is what the Air 2 should have been, etc etc and it'll be another cycle because by then the A8 will have a strong install base and the Air 3 owners will be waiting for developers to fully utilise their device to the max.
Even the iPad Air 1 feels like its got leg room to spare, when running the newest apps and games it never feels like its struggling. When I get to the stage where it's hanging, lagging, and incapable of running the newest apps I'll look at upgrading.
In the last 30 or so months I've spent over £1500 on iPads via iPad 3, iPad 4, and now iPad Air. I think it may be time to press the pause button and stick with one devices for more than a year.
Then again, come June when the corporate offer come up through my work to take a new iPad, who knows ...