Could we do a roll call of experiences so I know which ones work and which ones don't? Here are mine.
Dell Precision M6800: Avoid.
Supported Ubuntu: so ancient that Firefox
and Chrome wouldn't install without source-building
dependencies.
Ubuntu 18.04: installed but resulted in the
display backlight flickering on/off at 30Hz.
Dell Precision 7200:
Supported Ubuntu: didn't even bother.
Ubuntu 18.04: installer silently chokes on the NVMe
drive.
Ubuntu 20.04: just works.