Dave like I said in a previous post the keybed reminds me in between a Genos/Pa4x & Digital Piano action, took some getting used to
but certainly a pleasure to play you just have to think differently when your playing vs the featherweight plastic keys of the
S-series & Pa-series units..
So far I am exploring all features within the OS.....I was happy that it plays SMF directly from a USB without any limitations to folder size just scroll thru the songs, hit song play and play and sing on top.
What is already has inside style wise gives you enough to cover most genres easily even with the limitations of 2 variations
& 1 Intro/Ending which I don't need as I play my own most times anyway. Speakers & Vol are excellent too. I like the rubberized buttons too and navigation is easy as pie. The simplicity is enjoyable not having to worry about all the arranger stuff I'm used to....with the DGX660 you just play and enjoy....
most of the styles are the most popular Yamaha ones most players will surly recognize from units like the Psr S950 etc..I did have to buy a larger cover my AX stretch dust cover for 88 keys....
old one only fit 61/76 keys no big deal..
More to come ..

Take care..back to fun