As far as I am aware EMC Style works has not yet been updated to accept all the Tyros 2 Styles.
Also there will still be a lot of work involved after the conversion process unless the style works program has been incorporated (And optimised) by the manufacture of the instrument.
Giga sounds and other samples will not sound the same as Yamahas Mega voices, this means that even if you select the same sound names, you will still have to alter it (Or select another similar sound) to suit the style.
However don’t be disillusioned, as the effort can be worth it in the end.

Bill