I just purchased a Yamaha YPG625 keyboard and I think the grand piano is better on the Yamaha then on the Casio WK-3700. Having said that, I think many of the other tones are better on the Casio WK-3700 than on the Yamaha. One example is the draw organ.
I purchased the YPG because of the weighted piano keys and Grand Piano tones. I looked at the Privia 110 and 310 but decided on the Yamaha as it has so many more tones than both of the above and allows me to use it as an arranger as well.

-Linda

[This message has been edited by LindaFus (edited 12-28-2006).]