If you are wanting to move between styles and sounds quickly I find that the SD1 is no way near as quick as my Tyros 2.
Also the way it operates is behind the times, far too many button presses for my liking and the display screen looks like it came out of Noah's Ark compared to the larger colour screens on other models.
I do like the sounds and styles, no way near as good as the Tyros 2 mind in my opinion, but I'm selling mine as it's far too slow for my liking when playing live.
Good luck with what you get but I should wait for the new Roland E80 and then take the best you can afford.