I just picked up a new ESI-2000 about a week ago for $560 at Guitar Center. What a deal! Where to start? The ESI-2000 is the same exact machine as the ESI-4000, except it has 4mb less ram. The color is different too. They use the same exact OS. The bootup screen even says 'ESI-4000'. 64 note polyphony, ram upgradable to 128 mb using 72-pin simms. Unit also comes with 4 outputs, upgradable to 10. Not too bad for the $700 range. The filters are amazing. The ESI comes with 10 sample cd's, which are actually decent. The best professional sampler for under a grand, by far.
If you have any other questions, email me.