Question about piano tone quality of SX 900 and 700

[dogendo]

A question for PSR-SX 900 and 700 's owners : how good are the acoustic and electric (Rhodes and Wurly) piano tones of the SX900 and 700 ? ; is there a différence between the two models ? ; and how does the SX's acoustic piano compare to a P125 type mid-range digital piano for example?

Thank you in advance for your advice

Mike