I was hoping to get a printer with similar requirements. I end up to buy Samsung CLP-350N, a color postscript laser having ethernet and USB and good Linux support both by free and Samsung provided drivers.
I was happy and I recommended it also to others, UNTIL the first black cartridge was finished. The first one does not contain any DRM chip so I did not know the printer has DRM at all. The printer keeps an internal counter how many pages are printed with the first cartridge and refuses to print anything after a certain limit unless the new cartridge contains a DRM chip. The chip coming with the unofficial cartridge claiming compatibility with CLP-350N did not work in via ethernet. Via USB it might have worked according to instructions given by cartridge seller but network functionality was required. So now I'am quite disappointed with this model.
I would go for HP now. Its popular so it is quite certain that toners are available after 10 years - either from the HP itself or from unofficial sources.