I have the MS2000R (R stands for rackmount) and a MK-4902 keyboard that I got for a total of $800 (thats $100 cheaper than the MS2000, and the MK keyboard has more keys and handy features itself, such as presets). I am very happy with the synth and keyboard, the synth has a buttload of features and is well worth the money. It's cheap compared to other synths. The MS2000 does sound more trancy than anything else so if you like trance, it kicks all ***, otherwise try some others first. And unless you really need the convenience of a synth with built in keyboard, go with the rackmount, it's cheaper and better.
Mangazm