I'm a happy user of my second Tuxedo laptop after using the first for over 7 years, repairing several parts. I found their support very responsive and spare parts affordable. Your points are valid though. If you don't like their custom stuff, the device also works fine with a stock Linux install (Ubuntu in my case).

They're also the only OEM that replied to me when I was trying to reverse engineer a similar laptop to theirs. I think that alone should put them into a league of their own. Only two companies have ever properly replied to me when I asked about source code or hardware documentation: one is a chinese company, the other is Tuxedo.