i am also interested in this topic. i know o3bor has listened the e50 keyboard at musikmesse.
i think that are very few people until now that got the chance to play or listen a e50-e60 roland.
we might have to wait for couple weeks and then we'll hear some demos hopefully. they won t release the keyboard without putting some demo on the website i guess.
i am interested if the sound engine is the same in all 3 models, e80, e60, e50. somehow, i believe e80 has different (better) sounds, because the difference in price is too big, and the features are not that different.
we'll see...