Yeah, there are a fair few of us who have the XPS 15, and it’s wonderful.
I popped a 970 pro into the laptop before even turning it on. It’s super easy. Just a T5 and a PH0 bits and you’re all set. Definitely worth it, and I’ll say that Linux works wonders on the non-Nvidia models, can’t speak personally to the Nvidia variants.
Some of the people who have the higher models, with the 1050, complain about temps, so you’ll definitely want to repaste it with good paste. (this actually doesn’t void warranty, we’ve checked with dell support!)
This thread might be of interest to you as well:
Even with the thermal issues, I’d still say it’s the perfect laptop, and most of the thermal issues can be solved by undervolting by -150mv. I just don’t want you to get it and wonder why we didn’t mention the heat.