I've had a Dell Precision 5510 and now I'm using a Precision 5520. Ive run Ubuntu, but am currently running Fedora 29 on the 5520.
Fantastic machine. Best Linux on laptop experience I've ever had.
I switched to a ThinkPad due to the 5520 bottom mounted camera. I never thought I'd hate it so much, but we started doing lots of video calls at work, and it really became an issue for me.