I have played and owned many arranger KB's. The X1 was the first one where I could sit down and enjoy playing a ton of songs and find a multitude of styles to play them with!
The styles are not OVER DONE yet they're not simple and boring. It really is a difficult thing to describe?? I had the opportunity to play one for a few days (after selling my I30) and decided immediatly I would purchase a Solton! Because of the timing (intro of the SD1) I decided to order an SD1! Can't wait 'till I get it!!
The Roland, Yamaha, Korg are all pro stuff that sounds great BUT the Solton/X1(and I'm sure the SD1)move away from the pack and enter a different ZONE
!!It is not for everyone, nothing is, but IMHO it is worth the wait to see,hear and play the SD1.