Hi
As far as i could see and hear,the new SD1 is a far better keyboard than X1.
Very improved sounds,drumkits etc.,and the internal patterns is great too.
Many "live" features that you have to see,listen and try out by yourself,it's too difficult to explain it all.
The vocal harmonizer is the first one in a keyboard who is for any use in my opinion,and the mic-inputs is XLR balanced. There are 76 keys etc, but I guess you know about all this already.......
One thing is not good,the accordions sound terrible :-(
Anyway,I like the SD1 very much when i saw it demostrated on a stand/demo,and this is the first time I ever consider to go for any other keyboard than Technics.
Good luck with your new keyboard when you recieve it.
GJ