Which Mixer should i get?

I have been doing mashes and just having fun mixing music for a hobby nothing crazy, but i have been using a mix track pro for the past 7 months and I am looking to get something a little better that I can do more with, I was looking at the Traktor S4 and S2 but i dont know which one to get because the only thing i mix is basically edm, i read that the s4 maybe not useful for people just needing two channels, is this right? Does anyone else have any other opinions.
Thanks

Please do some basic research. More targeted questions will produce more helpful responses.