From what I know, they are one of the companies endorsed by the FSF, so I'm assuming they're good as in good with Linux and open source. For the quality of their products, I assume they work at least good enough. The specs of their PCs seem fine for the prices.

Overall, they seem to be good, especially good if you went far down the libre rabbit hole. I want to note here that they don't seem to donate to / sponsor any open-source organizations (like KDE), unlike Tuxedo.

Also remember that the stuff that's being talked about is probably more known around the community, so it's possible that just not that many people know about them.

I personally would probably buy their accessories, but maybe not their computers. This is my personal opinion that I made from ~30 minutes of research and a bit of previous knowledge from a youtube video I watched yesterday, you should make up your own with more research before deciding to buy from them.