Took a walk into town yesterday, managed to walk out of CPW with a nice shiny black Note 4. Very pleased!
So far, impressions are fantastic! It's fast, near enough the same speed as my previous Nexus 5, which is great as I was worried about Touchwiz still being a lag inducer, but it seems that it's just not an issue any longer, thankfully!
The camera seems fantastic, really enjoying the slow-motion feature already. It makes trampolining videos very interesting! The screen is also fantastic, I can't see a huge increase in resolution when compared with the N5, but the colours and everything are just incredible. The pictures/videos that came preloaded are just mind blowing how nice they are!
My only complaints so far are all actually issues stemming from not having root. The DPI is just far too high, everything is ridiculously huge! I just don't understand why icons and menus need to be that large on a screen with this much space. Then there's the new way Kitkat handles microSD cards - infuriating! I have some apps set up that sync a copy of my music, and my research files from google drive onto my phone. I'd planned to move all these onto the SD card, and free up the space on the phone. Apparently google doesn't want me to be able to use the SD card though. Ridiculous decision.
I'd wanted to avoid rooting the phone, just in case, but at this rate I think it's unavoidable sadly!