They re-tool completely for each arranger produced. Is the S900 in a PSR3000 case? No, it is not. Is the Tyros2 in a Tyros1 case..? No, it is not. The case for the arranger is the LEAST expensive thing to develop (compared to the electronics, sound and styles). We don't want a brand new Yamaha arranger, we just want an S900 in a 76 form factor.

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If the G70 and E60 were unsuccessful, but the E50 and E80 WERE, that argument (it's the key size, dummy!) would hold water. Way I hear it, Roland's 61 note arrangers are not much more market successful than the 76's.

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And finally, Yamaha (as pointed out) DO make 76 and 88 note arrangers. They just don't make very good ones. A $500 DGX is no comparison to a $1600 S900. Why do Yamaha think that low-end users need a 76, but NOT high-end ones? Where is the failed Yamaha product that proves their point? I KNOW you don't mean the 9000Pro..!

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Keep setting them up. Tired yet?