Yes Nigel,
I agree that the sound is great, but it was already present in the Tyros 4; I remember Martin Harris saying in a demo that they had sampled a vintage Telecaster from the Fifties (I wonder how much it would sell for...maybe the equivalent of ten Tyros 5) and they did a great job, no question about it. With the Tyros 4 Harris used this same sound to do a mean version of "Lay down Sally".