This is a hot topic.
I'll put in my two cents.
First, the djx-1 has many professional features. However, if you already have $300.00 available, save a few more bucks and buy a Korg MS2000/R.
It's about $900.00
However, if you want to go cheap then buy the DJX-1. The DJX-2 is a striped down version of the DJX-1. The DJX-2 lacks a pitch bend wheel and tons of other things the the DJX-1 has. Infact the DJX-2 though it has a midi out port, it can only send bulk dump information and patterns through it. It is incapable of controlling another keyboard. Until the DJX-2 came out, I had never heard of such an idea. The djx-2 does not even have general midi!
The djx-1 though has all the features of a professional keyboard including midi in and out, sampler, sequencers, digital effects, pitch bend, ribbon controller, and some nice sounds and General Midi. It cost about $150.00 presently.
You can find more out about the djx keyboards at the 13 inch djx user site. http://www.geocities.com/dj_white_rice