The Equinox starts pretty much where their previous synthesizer, the incredible-sounding S-series, left off.  This machine is absolutely full of features: here's a concise list of what's available (from the manual:

• An immense database (16 Mb samples) with over 1000 preset
Sounds and user memory locations to store more than
2000 new sounds. 112 Performance memories and a Groove
machine featuring over 1000 user-programmable Grooves.
• Unique Drawbar mode for instant access to vintage electronic
organ sounds using the 8 panel sliders as drawbars with
key-click, percussion, overdrive, etc..
 

• 250.000 event, 16 track sequencer with advanced song editing facilities.
• Advanced Sound editing facilities with 64 note polyphony,128 digital filters with resonance, up to 6 oscillators per voice, 3 Lfos and up to 21 independent Envelopes with 10 segment resolution.
• Sample Translator to create user-samples and load new samples of the most popular formats (Wav (PC), Aiff (Mac), Akai™, Kurzwail™, Smp, Snd. Future os versions will allow loading of Roland™, Ensoniq™ and Emu™ samples.
• Full MIDI implementation - The Equinox is the perfect Master Controller for advanced MIDI set-ups (32 MIDI Channel control, 16 programmable Midi Zones, 8 programmable Sliders, 2 programmable Wheels, 3 assignable Pedals).
• Flash-ROM memory which allows the instrument’s memory to be instantly upgraded by simply inserting a special floppy disk in the drive.
• The Equinox can be fitted with optional memory (8 Mb backed Sample RAM and up to 32 Mb SIMMs), an internal Hard Disk (2 Gigabytes) and a SCSI port (compatible with CD-ROM, Zip™, Jaz™ external hard drives).

As you see, there's a lot to this instrument!

What strikes me most about this synth is that it can definitely sound analog (just like its predecessor did).  While it's purely sample-based, there's something about the way the sounds come across, that make it sound warm, not digital.  The quality effects also help a lot in producing some of the best sounds on board.

This is definitely a strong contender to the other workstations that came out at the same time, like the Korg Triton, Yamaha EX5, and Roland original Fantom.  For some reasons it wasn't popular enough, apparently due to the first OS that could have been better.  By the time the OS was improved, other workstations had come out and this ended in the forgotten back of the music store - until now! :-)