I have one in my living room CP80 and CP70 in a studio. I use it for 20 years without amplification to work my piano and compose. For me it's ideal for the apartment because he really sound and feel of a real piano (it's a real piano with strings and hammers) The sound volume is lower than a true piano and I can play at night without disturbing the neighbors. If you move, a car and break a boyfriend and that's it. In my opinion the sound is much more homogeneous than upright piano and the sound is typical of the jazz piano. Ability to play chords without large troublesome harmonics. It can also connect the speakers to integrate with other musicians to beef.
I'm a fan of this model and I do not understand why Yamaha has not reissued the CP80 or CP70.