Actually Yamaha has had something like this for quite a while, which is NP-12 (Piaggero), but, frankly, I think they tried to hard not to make it too good. Then Roland released "Go Piano" (61 keys), with good sounds and 128 polyphony, I think it was and still is a rather nice product. Now Casio joined the club. In fact, I see that they all cost about the same, so I would probably go with Roland myself, looks like it even has some sort of recorded.