[Xperia Z3 Compact Q&A, Help & Troubleshooting] Krastinov:
EDIT: Damn, didn't read you already have a G3, curse my lack of reading skills.

I don't know much about the Z3C as I haven't had much contact with it besides playing with it at some store, but I suppose I can tell you a little bit about my G3

Pros:

+Screen size and resolution - it's just perfect for watching vids, playing games and browsing stuff in your bed. Everything you see is incredibly sharp due to the horrendous resolution. I can definetely say there is a difference between my dad's Z1 (it's FullHD, while Z3C is just HD so the difference is even bigger) and my G3 in terms of clarity of the display. You can literally read ant's-****-sized text.

+Camera - it produces really nice shots, in good surroundings it can give birth to magnificent images you will be proud of. And having the laser focus makes you feel like a James Bond... sometimes :o

+Performance - yes, the QHD sometimes makes the CPU a bit sweaty, but overall there is little to be desired. You may be disappointed if you expect your phone to switch to landscape mode in a blink, but for a simple user it is absolutely ok.

+Pretty and slim design - not as flamboyant as your favourite drag queen, but I really like the way it looks. Altough it is more like a matter of taste.

+Physical buttons placement - it may seem weird at first, but you will like it.

+Durability - I squeezed it many times in my pocket by sitting or kneeling abruptly, yet nothing happened and after six months my device still looks great. Also, the screen is really scratch resistant, there is no need to purchase any screen protector.

+Great standby time - it will live a looooooong life if you just leave it idle.

+Mod-friendly - easy to root, easy to flash, you can restore it no problem if you screw something up (no fear of permanently damaging the camera like in Z3C's case)

+Removable battery - you will love it if your phone gets stuck for some reason. Just pull the battery and all the bad dreams are gone!

Not-pros:

-Overheating - yep, sometimes it gets hotter than girls in your browser history. Hovewer, it occurs only if you push the phone to the limit.

-Need of tinkering - I mean, LG screwed up the software a little bit so you may want to get rid of some of the annoyances like screen oversharpening (it was so annoying that I've decided to root the device just to repair this one goddamn thing, I couldn't stand my mom's face oversharpened), heating, battery life, etc.

-Battery life - not as good as Z3C's, expect it to have 4-5h SOT and be battery hungry at the end of the day if you use it a lot. There are no perks like Stamina mode, though it can be dealt with through rooting or simply buying a bigger battery.

-Plastic - it doesn't feel as premium as the Z3, it emits some creaky sounds if squeezed, the back of the phone can get scratched if you place it on a harsh surface.

-Dimmed screen - not useless in a direct sunlight, but you will have a hard time reading the text on it.

-Not waterproof - unfortunately it's not as resilient as your ex-friend's head, you shouldn't try to flush it down the toilet.

-No stereo speakers - not like it is really needed on a mobile phone imo, but still.

So the way I see it... if you like small screens, perfect performance, topnotch battery life and water resistance, go for Z3C. But if these things aren't that crucial for you, then you won't be disappointed with LG's flagship child... oh wait, isn't G4 out already? Too lazy to check it, but this can only result in one thing - price drop.