I completely disagree. The Air 1 was the worst iPad I've owned. It was a worse experience than my iPad 3 - the 3 was slower, but faaaar more stable thanks to 32bit/1gb ram.
Apple should never have released 64bit devices with only 1gb ram. It was enough for single app performance, but the moment you press that home button and do something else, bam, it was a crap shoot what happened to your last opened app. Fine example is podcasts - I'd bring up CC to pause podcast, answer an email or visit a website, bring up CC to unpause podcast....only to find podcast app flushed, and it defaults to music playing. Equally, I had to copy any text I'd inputted on a webpage or email, because it was nearly always gone when I returned. Terrible. This didn't happen to my much older iPad 3.
Same negative applies, to a lesser extent, to the 6 Plus.
The 64bit 5S was passable with 1gb ram, I have memories of it as a good experience.
I've never owned an iPad 3 so I can't compare to that device (though I know from multiple reports that it performs badly) but the iPad Air ? Oh my god... this device performs like a piece of ****.
I've never upgraded it to iOS 9 (because I knew it would create more problems than it fix) but even on iOS 8 it was horrible.
Animations were laggy, the device was often unresponsive for a few seconds after doing an action (like a tap or a double press of the home button) : a huge laggy mess.
Let's talk Safari now, which I think was the worst part of my experience with the damn "There was a problem on this page so it was reloaded" error that happened ALL THE FREAKING TIME. Also tabs performance was ****, I could not open more than one tab without the other needs to reload. Safari was also very slow at loading pages, it was constantly moving the page up and down so I was always missing my tap.
Multitasking was very bad too, I can't belive this device have 1GB of RAM, I could not have more than 2-3 (light) apps open in the background (sometimes it was even wrost, only 1 app) without needing to reload. Even more unbelievable, sometimes my music playback (from Spotify or the stock Music app) just stopped working for no reason and when I re-opened the app, it needed to reload.
And did I talk about resprings ? This did not happen all the time but very often, when I jumped into the multitasking, the device would respring for absolutely no reason.
I can't believe how bad this device was compared to the iPhone 5s which have almost the same specs and performs like a champ, no issues at all.
Also, I should mention that when I bought the device it was already running iOS 8 so I never had the chance to have it running iOS 7 and I don't know if the iOS 8 update crippled it or not.
Anyway, I could not stand this iPad anymore so I recently pulled the trigger and bought an iPad mini 4 (I wanted a smaller form factor too) and I don't miss the iPad Air at all. This was one of my worst Apple experience I've ever had with the iPhone 4 on iOS 7. My 3GS experience was also bad but given it's age and specs, I think I was just expecting too much from this device so I can't really blame it.
By the way, sorry for the off-topic but I needed to quote this post because I believe it's the first time I hear someone with the iPad Air that had the same awful experience as I did.