4k notebooks that run games at ultra at high enough fps are quite rare and quite a lot more expensive.
If you want 4k for stuff that isn't gaming, then you should look elsewhere, as this one is not the best monitor available, and why would you pay for a gtx1070 if not gaming?
If you game at 1440 or 1080, then no point in getting a 4k monitor, as it will consume more power that will be wasted (ledd battery life).
The interesting thing to see here is that a standard 1070 doesn't quite cut it for solid 60fps even with G-Sync on Ultra. Still, not a bad laptop but needs about $300 off the price tag to be really competitive.
Edit: I also wanted to say thank you for a nice review but also ask if possible to maybe update the game review suite with some more recent games such as Battlefield 1, Resident Evil 7, Watchdogs or perhaps just slightly older like Doom, Witcher 3. Those first 3 games are often mentioned in threads by either people trying their first builds or looking for gaming laptops. I have a number of the older games, they're awesome and demanding, but it'd be nice to see how new tech matches with more recent games.