Me too. I'm running the Dell Precision 5520 right now and I've been pretty happy. Tho, deviating from the stock OS (Ubuntu 16.04) is not a very easy path. For that reason I may go back to System76 for my next buy.
I have a 5520 too, but one I got via the outlet store, and which came with Windows 10, not Ubuntu. I've since partitioned it and have Arch running on it too. Was completely painless, and everything works. Which distro are you having issues with, and what are the issues?