Killer sound, great key action, tons of features. Perfect for your home studio or gigging, tons of functionality jam-packed into one unit. It has three different sections which can be independently controlled. A number of sound patches are installed by default, and lots more available online. It's a pleasure to use, aside from the nice hammer-action of the piano, the multiple knobs feel good and provide immediate feedback in the display.
The piano engine includes not just grands and uprights but also includes electric pianos, digital pianos, clavinet/harpsichord. Lots of fine adjustments to each piano sound including touch sensitivity, layer detuning, bright/soft timbre, string resonance, and even noise from the sustain pedal. I have the additional Nord 3-pedal sustain unit which includes Sustain, Sostenuto, and Soft pedals and works perfectly with the unit. The sound quality is incredible, from the softest touch to the loudest key banging.
The electric pianos (both fender rhodes and wurlitzer) sound great too, as does the clavinet. there's also harpsichord and digital piano, but i haven't used these much.
The organ engine comes supports the standard 9 Hammond manual drawbars, chorus/vibrato (C1/V1 through C3/V3), and percussion (2nd/3rd harmonic, fast/slow, loud/soft). A built-in Leslie preamp + rotary-speaker emulator really make the organs scream! Aside from the definitive B3 organ there is support for Farfisa and Vox Continental (with the drawbar controls adjusted as appropriate for each), as well as two flavours of pipe-organ (again with drawbars modelling the different stops). The dual-layer functionality allows you to use a keyboard split to model the Hammond's upper and lower manuals each with separate drawbar control, just like the real thing!
The synth section is amazingly featured for fitting into such a tight space. There are choices between sample synths (with a variety of sampled sounds installed by default) as well as the classic synth sounds with base Saw, Square, Pulse, etc waveforms as well as formants, SuperSaw/SuperSquare, etc. These can be modified using Attack-Decay-Release dynamic shapers, Low-Frequency Oscillators, and a selection of High/Low/Band pass filters w/ resonance. The amount of control here is mind-boggling for fitting into such a small bit of space on the keyboard panel.
The Nord Stage 3 supports keyboard splitting, so you can have up to 4 different regions assigned to different patches. One limitation is that the splits are a bit limited to 10 distinct points on the keyboard (between E/F and B/C spanning a few octaves).
The sounds can be routed through different effect units, but it seems only one engine at a time can be sent to each (ie, piano, organ, OR synth but not multiple). Effects include Tremelo, Wah/AutoWah, Phasor, Flange, Chorus, Ring Mod. There's also a Digital Delay, Reverb, 3-band equalizer (with adjustable mid frequency), amp simulation, and compressor. There's a comfortable pitch-bend stick, and even a morph wheel that can be assigned to multiple parameters and tweaked live.
I've had this for about six months now and love it, and I'm still discovering new features. I use it in my studio most of the time, but also take it with me to band practice and gigs. One other note - at 20 kg this thing is HEAVY, and may be wobbly on some less-sturdy frames. I've used it with the standard Nord piano legs which provide a solid base, but now that band practice has started back up again I've switched to using a stand so I can just grab and go. I've also bought the accompanying Nord Soft Case, which comes with wheels and makes carrying it a breeze.
Like I said above, TONS of functionality and amazing sound packed into one tight keyboard!