Between the two, I'd choose MS-DOS based product all the time, especially if this was _just_ MS-DOS, no 3rd-party drivers.
MS-DOS is actually amazingly small by modern measures, it offers less features than many modern RTOS'es - it's basically file system, program loader and _maybe_ some interface points for 3rd party drivers. Display, audio, external devices - it's all up to your software to decide. Your MS-DOS display driver will never break because MS-DOS does not provide display drivers.
This is good for keeping things running as long as you don't need to upgrade hardware.
Comments
Between the two, I'd choose MS-DOS based product all the time, especially if this was _just_ MS-DOS, no 3rd-party drivers.
MS-DOS is actually amazingly small by modern measures, it offers less features than many modern RTOS'es - it's basically file system, program loader and _maybe_ some interface points for 3rd party drivers. Display, audio, external devices - it's all up to your software to decide. Your MS-DOS display driver will never break because MS-DOS does not provide display drivers.
This is good for keeping things running as long as you don't need to upgrade hardware.