To me THIS is, as Frank Zappa would say, the crux of the biscuit. At this pointYou also have to consider that probably some part of 'the Roland sound' lies in the hardware being used (D/A and so on). That aspect could probably be modelled, at an additional developing cost.
there are quite a few VSTi's that can load .syx patches of hardware synths. Do they have that same sound and feel as when loaded in the original hardware synths....almost never IMHO.
