OK, if you're following - my EA7 has morphed into an SD7. My initial thoughts are positive, but it's way too early to change my avatar.

Positives:
1-sounds great - speakers are powerful
2-feels great - solid, weighted (but not heavy) keys
3-navigates well, not my fav, but not bad
4-most features you'd want are easy to get to
5-extra mic, or guitar input - YAY
6-intuitive sliders - well labeled
7-2 media players

Negatives:
1-larger than I'd like by 6" - makes it cumbersome to load, and tight on many stages. A case for this beat will make it impossible to fit in my trunk side to side. Don't want another minivan, don't want to slide it in longways. I want it to fit in the trunk.
2-no hard button for vocal harmony - not assignable to standard f/s
3-I'm guessing that most arranger players have WAY more free time with the left hand than the right, so splitting the controls on either side of the screen, while attractive, make it difficult to make some changes that I'm used to doing with my left hand
4-it's a tad heavy, but built very well. It's solid, pro looking, and attractive

These are my impressions after just a few hours with the unit. I spent about 2 hours updating the OS ... you have to do one at a time, and this one needed 5 updates. Future updates will be a snap.
I haven't even started to write a registration, or custom patch, but if push came to shove - I'd take it on a job tomorrow, and sweat through it.