Not the person you were replying to, but anecdotally my XPS 15 9550 has been nothing but a nightmare.
It's on battery #3 from the battery swelling issue, a lot of backlight bleed on the 4K Display, coil whine in the power supply (went through three of those), three DC jacks (might need to be a 4th soon), the infamous VRM/throttling issue, and to top it all off I had the main board replaced within the first two years because of a firmware problem preventing Windows from activating. Less of problem with the system itself, but during that mobo job Dell replaced the 512GB Samsung SSD with a Toshiba 1TB and R/W speeds dropped to ~1/3 of what they were before. Also anecdotal but a buddy of mine with a 9560 has gone through more or less the same issues, sans the firmware problem.
They look so appealing on paper (which is why I chose it over a MBP), but there's just something about them that feels proof-of-concept, like it's an unfinished product that was pushed out too quick. I wanted to give Dell another chance, having gone private three years before and having seemingly improved their build quality. When you spend $3800 on what is supposed to be the best-of-the-best and it turns out to be the headache of a lifetime, it leaves a really sour aftertaste.