Got me an SD5, installed the vocalizer and a 2GB SSD (no problem, 17,59€!) - but I may have to sell it ageain. I am the guitarplayer and my wife is operating the keyboard. So she tells me that it sounds good, but she is not willing (so far) to accommodate to a new apparatus. She does well with the MS100 - no mistakes. I know that I have to tweak my Midis, I don't use fabricmade styles, always do them "my way", but I think it would be a step forward.
I hope she'll let herself convince by the use of the vocalizer...