Debian-friendly laptop

[George Shuklin]

I'm trying to choose between Purism and System76, and, as far as I 
understand they both supports linux very well, but..

Which one is better? Or, may me I missed and there are other coreboot 
(no ME) vendors with high-grade Linux support?

I have a negative experience with XPS13 DE (which is shipped with 
Ubuntu, but even with all tweaks and random sleeps they added to vanilla 
Ubuntu, is far from perfect in Linux support)...