T550. Probably the best laptop that I've ever laid eyes on. I can switch batteries while it's running because it has two batteries. I get a total of 16h of normal-duty work time out of it. It has 16 GB of RAM and a NVMe as well as a SSD, 3K screen and a pretty good touchpad and usable keyboard.

I think the build quality is nice, it has a serious appeal to it and has a nice weight and feel to it when carried.

I'm a 100% Arch Linux based developer doing all kinds of work.