I'll start with all the bad features: it's big and... That's as close to a bad a feature I can come up with.
The second screen, which some laugh at, is great! Think of it as a configuable set of widgets that shows favorite contacts, today's agenda, music control, favorite apps, and running apps (easy switching and closing). And imagine this set of widgets always being available - from the home screen or in an app. And when the screen is off it still shows the time so you don't have to turn it on. Plus to save battery just turn the phone over and the second screen turns off. Great feature set.
Main display is great - bright and crisp. Never an issue reading it outdoors or in. Note the main display and second are really the same hardware.
Fingerprint scanner works great until you put some cases on, but T-mobile and Verizon have already pushed updates which solves the issue. Scanner works 98‰ of the time on the first try now with a case on.
Oh and it's fast - so much faster than my rooted S3. Thanks to 4GB of system memory and 64 of app memory. Add an SD card and this is a beast!
Nothing bad to say about LG launcher either. Some nice features. No plans to install Nova my go to launcher or Google launcher.
Sound - music, speakerphone, calls all are great. Have not really tested hi Def audio yet, but I have heard it's great.
Bluetooth connects everything and is crystal clear. Navigation is great, Gps location so quick! Note that when the phone is horizontal and wearing polarized sunglasses the screen is black - so it must be vertical.
Battery life is unbelievable! Even with exchange email, Gps on, Bluetooth on, twitter notifications, etc (no Facebook, not a constant twitter scroller) I am consistently getting 30 to 40 hours between charges with 4 hours of screen time. I can use nav for both ends of my 45 minute commute and still have 55% battery left when go to bed. Right now it's been running 37 hours, almost 4 hours of screen time, and still have 27% or 9 hours left. Just amazing.
And they say it's built like a tank. Search for V10 tests on YouTube - guy drops it, puts a lighter to it, scratches display and it passes with flying colors.
All in all glad I went with the V10 over the other phones I was looking at - G4, S6, S6+, or Note 5.