I am not sure if this is what you want to know, but: - Debian.org or Ubuntu.com officially does not support any of those boards/boxes, - Armbian userspace has many small but vital performance or security adjustments, - Armbian fancy some kernel development and a lot of its maintaining. Debian relies on upstream sources for ARM hardware which can be years behind and/or lack of many functions, - Armbian userspace is lean, clean but 100% Debian (or Ubuntu) compatible - many s