In that case, the rd300nx only acts as a controller for Ivory II, which I believe is still top dog.
I believe it feels more natural to a trained pianist.) But it’s no match for a really good virtual instrument when I’m working with my DAW. I think the RD’s grand piano is pretty good for practicing, playing at night with headphones and for the stage (IMHO the action is even better than that of a typical dedicated 88-key weighted controller. I use an RD 300nx, basically the same thing (with a smaller sound ROM that includes a more limited selection besides the pianos, which are identical to those of your 700nx.)