Depends on whether or not you want to hit pads hard to register an input.
I'd recommend anything not from akai unless you got a sturdy surface that can take all the force then I'd say akai's worth it.
So...gonna have to say maschine.
i havent tried the ren, but i own a maschine and i love it. The workflow is ultra fast and smooth. I dont see how another gear could possibly be better, and its cheaper than the ren too. Only thing i dont like about maschine is the sequencer wich i think may be better on the ren. I would say get maschine unless u got money and is accustomed to mpcs