Based on all the comments on HN about how great Thinkpads are supposed to be with Linux, I bought an X1-Extreme some time ago. From my experience, Linux support for Lenovo devices is terrible. ACPI, power management, and UEFI are consistently causing problems. Grub has an issue with the 4K display, causing it to render at about 1 FPS. The dual-GPU (Intel and nVidia) situation is unworkable under Linux. Suspend on lid…
Last time I got a new laptop, I simply ordered a Lenovo Thinkpad (X1 Carbon, not Extreme) with Linux pre-installed. I am past where I want to tinker to get the hardware and software working together, but do prefer Linux as my daily driver. I haven't had any issues with it, but I also got a relatively simple setup. I've ordered a Linux pre-installed Dell in the past with similar fine results.
ThinkPad battery life could be a bit better, but that's my fault for choosing the 4k one.