You can hear how you have to make sure your beat grids are good and bla bla bla...truth be told, the sync on the 2000nxs sucks in comparison to a DVS like Traktor. I can't speak of the 900 nxs as I have never used one but the whole 2000nxs fw could use a little touch up!
I like my setup so don't think I am bashing, I just thought you would rather hear the truth vs the song an dance.
Just my 2 cents.