Mike,
I asked a similar question regards interfaces with multiple outputs in this thread - Recommend a compatible audio interface (2 in 4 out) - Cubasis - Steinberg Forums
The list of compatible hardware on Steinbergs site is by no means exhaustive and I personally think it would be good if Cubasis users could post details of their audio/midi hardware and some information.
One of the replies I got was in relation to the Akai EIE interface and stated that although there are 4 outputs, Cubasis could only (appear) to address the first stereo pair. This is information well worth having before going out and spending your hard earned cash on something that won’t work to its capabilities because of (presumably) issues with Cubasis addressing the hardware.
So, as I say, would be good if there was a sticky thread were end users could give some insight and opinions into the hardware (though all of this doesn’t actually answer your question… sorry) 
Cheers
Stevo…