System 76 has pretty good customer support and help entry level folks enter the *nix market, which is cool. Their cases are kinda poop quality tho.
In particular, I like that I can undo a few screws and then lift the case.[a]
In terms of build quality, it's neither better nor worse than those of most other manufacturers.
[a] See here: https://www.youtube.com/watch?v=eUfZO1llNXY
:-(
Their support has been fantastic, and although I switched back to other machines - I still would buy one.
The bang-for-the-buck on the guts was really good (cant comment on the value of this Threadripper box though...)
As an aside; the Michael Dell "How I built this" podcast ep is worth a listen...