I learned to mix on the DJM600. (a friends) It seems kind of half way between a studio & dj mixer. The beat-matched effects are nice, but not variable enough, and VERY awkward to set up to a Kaoss pad.

I bought my first mixer , Numark Matrix 3, and am very pleased. Nice large differences in eq. settings, kill switches, and punch buttons. Not really suited for production, but for a dirty mixer that sounds good and performs well it's the Dog's Bollo(x).