go at least 16 channels dood, you will be happier in the future. infact just use cubase's mixing facilities for now until you can afford a half decent desk. that way you won't have to fork out money twice when you realise the cheapie, not enough channel one isn't all its cracked up to be....

as for mixing differences, its just the sound difference and feel in the end. cubase probably offers more flexibility at the expense of that "analgoue" sound.