[Nexus 5X General] zepeters:
Ok, long post too... bear with me...

So, I had the exact same issues as you described. I loved my N5 and I've been using it daily for the past 2 years or so. The main reasons I wanted to change phones was battery life and the cameras, both rear and front facing. I do agree with you when you say that the N5 snapped some fantastic shots though. HDR+ really works wonders.

I considered a lot of options such as the Moto X Style/Pure, Nexus 6P, LG G4, Xperia Z5, Galaxy S6 or the OnePlus 2, but they're just too physically big. Can't carry around a phone that big. I'd have to buy new trousers because I wouldn't be able to fit it in any of my pockets :P

Also, Z5 and S6 are way too expensive and I find it morally wrong to spend so much money on a phone... personal thing...

After a lot of reading and thinking, I did get the 5X in the end. I'm in the UK so I paid slightly less than 530€ (£350 which is around 485€). I must say that I'm definitely happy with the upgrade.

As for the camera, when you say it doesn't perspire quality, you're completely wrong. The camera on this phone is FREAKING amazing, the quality is outstanding and the focus is lovely! The sensor captures a LOT of detail! I mean, A LOT OF DETAIL! Can't really say about the colours cause I'm colour-blind (lol), but I find them spot on (a little bit on the dark side perhaps but nothing to worry about, you can always bump up the brightness in edit mode). The aperture is quite good which makes the macro mode fantastic as well (depth of field related). Even though I got some decent shots with the original N5, this camera is on a completely different level, quality wise! As for speed, I find the camera app a little bit to slow at times but this is a software issue rather than an hardware one. The focus is fast and accurate. Most likely the app slow down will be addressed in a future app update.

Front facing camera is also quite decent. Wide angle is awesome for selfies and it also captures a lot of detail. Coming from the 1.3MP camera on the N5, this one is a welcome improvement, trust me!

As for battery life, don't get your hopes up. Don't get me wrong, battery usage is way better than the N5 and it does last a full WORKING day (which I wouldn't get out of the N5... I'm a very heavy user) but it's no Z3/Z5 compact. I'd say you can get 30/35% more usage time on the 5X. While it might not seem a lot but I've been getting a lot more Screen on Time and standby usage has also improved. I feel like doze works way better on the 5X than on the N5, probably due to the revamped hardware (note that always on sensors on the 808 SoC are much more battery efficient). Quick charge works wonders too! Charge it for 10/15 minutes and you're good for another 4/5h of usage. Perfect for when you have a night out, just charge it for 10 mins before leaving work and you're good to go!

Chipset-wise, while it might not seem a worthy upgrade, I have to say that the 808 performs exceptionally well. The 64bit architecture DOES MAKE a difference although by looking at the specs on paper you won't really tell. Even though my N5 was mostly snappy, it would lag and struggle at times. I've yet to experience that on the 5X and I have the exact same apps/setup I had on my N5. Definitely an improvement on performance too.

As for the rest, it's pretty much the same experience as the N5. Build quality, android experience, sound (no stereo speakers, bummer, but it's the same as the N5 so...), screen quality. I was happy with what I had and I'm happy with what I have now ;)

By the way, two features I didn't care much for were the fingerprint sensor and the ambient display. While they may not be deal breakers, both things are quite a nice to have. Regarding the fingerprint sensor, its position is perfect and it works almost flawlessly! Also it's fast... like, insanely FAST! The ambient display helps battery and it works good, not great but good (doesn't always kick in perfectly). I'm guessing this could be addressed on a future software update as well. Again, it's not a deal breaker but it's definitely a great addition to an already good phone.

Sorry for the long post, hope it helps ;)