I love my Dell XPS 15 9560, upgraded it to 32GB Ram, 1 TB SSD. Use it on my desktop with dual 32" 4K monitors attached to the Dell docking station with the laptop closed. Ubuntu and Windows works great.
The key is the GeForce 1050 with 4GB in it. That just rocks. The CPU is good as well: 7700K.
It is also very light, thin. This was actually the main selling point for me. Because I bring it everywhere with me.
I've had it for a year. (Also I have never had this coil whine issue that some mentioned - for me it seemed like FUD, but maybe it affects someone.)
There is an updated model coming out in a month or so, same design, just updated GeForce 1050 TI and a 6 core Intel Core i7 8xxx processor.