Yes the update is 'coming'. Meanwhile the M8 has already started to receive the update. It will get the new Sense update after the M9. You can also flash it to Google Play Edition to get the latest updates OFFICIALLY. You cannot even root the Z2 without destroying its already terrible screen and camera thanks to Sony's DRM policies.
G3 has a bigger, better screen in a compact body (Screen-body ratio). It also has a far superior camera and it's also receiving the 5.0 update.
The Z2 has a washed out screen with poor viewing angles. Are you seriously one of those who run after PPI? Maybe you are so you're clearly not the right guy to talk about screens here. Colour accuracy, viewing angles, contrast ratio are what matters. M8 has THE BEST LCD screen on any Android phone. Don't believe me? Go read any review for the Z2 and the M8.
Yes we all know how great the resale value on the Sony phones is.
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Nexus 5 can be had for 35k for 16GB. It's a killer phone for its price.
Umm.. yes you can. All you have to do is make a backup of the TA partition. But you obviously won't understand any of it because you don't even know what it is. I never said I run after PPI, I just mentioned it in my post.
Secondly, you had nothing to say about the camera of the M8 because you know its crap.
And about the resale? Well if you ever had a Sony phone, you'd know. While your head was stuck up Tim Cook's butthole, you might not have noticed I had 3 Sony phones. All of which had great resale, but on 12th December 2011, I sold an HTC Desire S (which I got from Brightex for 36k), a few months after it's launch the same Desire S, got the highest offer of 8k in the local market and got sold for that amount.
Whereas, my Xperia U (bought for 14k, sold for 11), Xperia Z (bought for 37k, sold for 32) and a relatives Xperia T (bought for 29k, sold for 26). I don't see that MUCH of a loss here. So I really don't know why you're whining.