I owned Maschine for a year and it is great for a beginner or professional - lots of sounds, easy to put together beats etc. My brother had an MPC which he loved and said he would never part with, Both are excellent at sampling and creating new sounds.
Along came Push - Obviously this is restricted to Ableton users only, which I was. It opens up Ableton on another level and my workflow is soo much quicker. I introduced this to my bro also and he bought one within 48hrs leaving his MPC behind!!
If your an Ableton user then consider Push.
If not then MPC or Maschine are both great - personally i like Maschine due to Library available, easy to use software etc. lots of great youtube tutorials also.