Don't know if this is mentioned before but for those with an Ipad and Iphone Yamaha has a great free app called Yamaha synth book. This app contains a very good sounding synthesizer called AN2015.

Check https://itunes.apple.com/us/app/yamaha-synth-book-us/id953322768?mt=8

The AN2015 uses much of the same code as the reface series... and much of this will probabl;y find its way to the synthworld feature of Tyros 6, which makes a perfect combination with the DJ styles and features we now have seen in the PSR S series...

Also this technollogy will feature prominently in the upcomming Montage instrument (motif replacement)

and yes, its very good...