Points to consider:
1. Apparently LTE signal reception is great on the V20. That is an issue that hurt the Note 7. Note 4 has 10 dBm better signal in mid to weak signal areas (huge). If the V20 has great reception, that will help battery life in non strong signal areas.
2. Make sure you take a spare battery with you if using the DACs to push high impedance headphones. Physics wins out and the battery is the loser. Takes lots of relative power to push wired headphones not intended for portability.
3. Judging any device during the first day for smoothness can be misleading. Best to hold judgement a few days until device set-up has settled. Ditto for battery life.
4. In regards to the navigation bar (I agree it is annoying wasting 15% of display space) LG has the option to hide the bar in apps via a display setting option. You can flag the apps you want the bar hidden, but does it work for all apps, or still gives the black bar minus the nav buttons? That would defeat the point. All apps can fill the display, since Samsung devices do it with capacitive buttons. Should be no difference if hiding the buttons.
5. Best to get a case to reduce chances of water frying the device. The display would be the first thing to short out if water gets in the case.
6. BB has in store $200 credit (no contract required) for any device as long as not cracked and can power up. My G1 will be sacrificed for a noble cause. I go to BB a lot, so will net the device down to about $512, plus the mail in free buds.