I'm quite happy with the current group of arrangers. I could easily use any of the top or middle line from any of the companies.
It comes down to features and ease of use. They all sound good.
I've always preferred Ketron drums. Korgs are good but can't really sound quite as good as the audio drums of course.
No problem with Roland drums, but their arrangers leave out some invaluable features such as simple break/fill. How can they not incorporate that, when it has been a feature of ALL other brands since their inception?
I do prefer everything built in: great harmonizer, text and lyrics display, large color touch screen, multitude of styles available and great sounds. I prefer joystick, but wheels are o.k. if they are properly located. User-assignable buttons or sliders are great. Ability to use a multi-switch foot pedal is essential.
Other people may have different priorities, but I'm thinking whatever those priorities may be, they are pretty much available these days.
They type music I play (and the vast majority of arranger players play) calls for great emulations of traditional instruments ranging from pianos to brass to woodwinds, organs, guitars, even vocal sounds, etc. Few of us are interested in creating or using synth-type exotic sounds, although there are a lot built in to modern arrangers. Other than auditioning them, I've never found a use for one in reality, because I don't play the type of music that calls for them. I think the market for a hybrid keyboard would be very limited, but then there may be a NEW market that could be created that would bring younger people to the fold.
Rarely a week goes by that I don't have a musician ask about my keyboard, remarking that they didn't know such technology even existed.
Sorry for rambling. Can't wait for the SD7 to arrive!
Maybe it will keep me alive a little longer! My boat is 16 years old, my Expedition is 8 years old, my golf clubs are several years old, crap even my young wife is getting older, but the TOOLS of my trade WILL be current and the best available to suit my needs!