Thanks James (and Ville).

James – your answer seems a bit vague. What I want to know is this:
What is the maximum sustained DC *measurement* rate that can be logged, with each measurement consisting of two DC readings – voltage & current, and each measurement being accurate to at least 0.5%, and each measurement being spaced apart by a precise and equal time. Don’t worry about buffers – that’s an implementation detail that I don’t care about – I want *you* to factor that in when you give me the high level answer that I am seeking. ;^)