Frank,
I have a VA7 and was thinking to buy a second keyboard; that's the reason why I was asking you for a comparison. I have tried the SD1 last year and was disappointed to hear a crackling/hissing sound that later I came to associate with cyclic effects like chorus and leslie simulator. I hope that in the latest OS Ketron has fixed this problem. The noise, however, could be heard only through headphones, but still the VA7 had a much cleaner sound and for that reason I went for Roland.