I will be christening the 900 tomorrow; wish me luck. I haven't added anything to the Songbook yet and all my style songs are marked in grease pencil in my folder. SMFs are loaded on USB just like in the Yammy. Haven't practiced with the harmonizer, but feel confident it will work as I expect.
It's only for an hour, but I'll have a good read on the pros and cons of the board and my needs for more prep.