I liked the organs on the Roland better as well; more authentic to my ears...also the fact it has the sliders/drawbars for easy access.
Otherwise, it's a kind of apples to oranges comparo as the Roland has 76 keys, no vocal harmonizer and no speakers, where as the S950 has 61 keys, a VH2 and a powerful set of onboard speakers.
Personally, I think the Yamaha PSR-S750 (uses same great speaker system as S950) is a much better deal if'n you don't need VH, 76 keys or gimmicky audio drum styles.
Again, as with the Korg vs Yamaha...choice is personal and subjective, and I could easily gig with either BK-9 or S950.
Ian
PS...the BK-9's Chord Sequencer does not respond to transposition...very big flaw in an otherwise useful feature in my opinion.
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Yamaha Tyros4, Yamaha MS-60S Powered Monitors(2), Yamaha CS-01, Yamaha TQ-5, Yamaha PSR-S775.