Biface- The MS2000 offers some of the functionality of the MOSS board- yes there are some hot sounds already programmed but it is not the most powerful virtual analogue synthe on the planet- the MOSS board and Z1 are much more flexible in terms of raw synthesis power.

What are your priorities? If you nee a vocoder you can't do that on the Trinity with an external source. What about checking out the Triton. You can put a MOSS board into that board and use it's sampling inputs for the vocoder also (and it sounds great!!!!).

The MS's 4 notes of polyphony won't get you very far at all! I really do like the MS but I wouldn't have it as my only sound source.

You have other non Korg options which are way more flexible (and more expensive) in the vitural analogue synthes arena- check out the new Novation stuff with built in inputs and vocoder. Also Access virus and Yamaha CS6x with added VL and AN boards. As you can see- alot of options!!