[Galaxy Note5 Q&A, Help & Troubleshooting] walrusmonarch:
Alright, here are some of my thoughts on the phones :) :

I've had the 6P for about a month. Sending it back actually.

It is taller than the Note, and heavier. The metal feels nice, and the stereo speakers are awesome, not quite as good as a Moto X, but close. The Note's speaker is actually pretty decent as well, it will just be firing off to the side rather than towards you like the Nexus, but its not dramatically worse or anything. Battery life was comparable to what I see from the Note, some days better, some days worse. The UI is blazing fast, more importantly it is consistently fast, without the occasional judders you might see on the Note, especially when scrolling. It is running stock android, well Google's idea of "stock". So there aren't as many features as Samsung likes to put in, no multitasking like the Note, and obviously no s-pen.

The camera is fantastic, especially with HDR+ on, but it really suffers from the lack of OIS in 4K video. In 1080p, it has EIS, which does a decent job. I noticed it tends to capture more light than the Note 5 in low light videos, but it will be a bit more noisy. The Note tends to over expose a bit to get more light in some shots causing some bright lights to be blown out, while the 6P will do a bit better job. However I did notice in most shots, the 6P sort of under expose, and you get an overall dark shot, sometimes it is darker with HDR+. That may be fixed with an update. The Note produces warmer images in my opinion, while the 6P leans toward a slightly cooler temperature. Obviously, the camera app on the 6P is pretty simple and straight forward, but does not offer the many modes and manual controls you find on the Note. Third party apps can help with that. Overall, as far as the camera is concerned, I prefer the Note. It has slightly softer details and warmer colors than the 6P and just looks more pleasing to my eyes, not to mention, the Note is very quick in opening and capturing the images. Double clicking the power button opens the camera, so that works fine.

Front facing camera on the 6P is pretty great. Didn't use it all that much though.

Display is slightly better on the Note, but if you set it to AMOLED photo, it looks pretty much the same as the 6P. A very nice panel on the 6P, really.

I seemed to have slightly better cell reception with the 6P as well on T-Mobile.

Finger print sensor is far quicker and more accurate on the 6P, but it is on the back. Makes it a bit difficult to use when placing the phone face up on a surface. On the other hand, it is really easy to unlock while taking it out of your pocket.

No wireless charging on the 6P, but it does support faster charging speeds with USB C's power profiles (5V @ 3A) and a USB C charger. Usually took about 90 minutes to charge from empty to full.

The Nexus 6P is a fantastic phone, but in the end, I missed the added features of the Note, especially the s-pen. If you really don't care for the extras that Samsung adds and don't really care about super stabilized 4k video recording or manual controls on the camera, etc., then the 6P is great choice. Being a Nexus, you will get timely updates as well. My 6P was already on 6.0.1. If you are keen on trying stock android, this is a good phone to do so.

As for the V10, I had one for about a day, so I can't really say too much about it :) It's built like a tank. The camera is fantastic like the G4. Removable back and expandable storage always a plus. The second screen is kind of useful I suppose, but I didn't have it long enough to really tell. I really didn't like LG's skin though and it seemed like the dpi was set by default to a value where everything (UI elements, etc.) are just hideously big... You can change the font size, but the UI elements will still stay just as big...

The V10 is basically a beefed up G4. If you loved the G4, you will love the V10.