
This is a long post: The gist of it, if you have a case of TL;DR is "I'd really like a Solaris, but I have space for an 88-key weighted controller and would like to have only one device".
A bit of background: I've got a small project studio. I used to have a large project studio that was more akin to a museum, but moved house, and frankly I was getting fed up of spending more time trying to work out how to make MIDI behave on things like D-50s and TX816s and worrying that my old analogue things were going to die of old age (my AlphaSyntauri used to make me extra nervous). I've sold a lot and bought new stuff, and the current state of play is in my signature.
I'm really happy with what I have, but the Trinity as a master keyboard is suffering from old age - the AT strip is failing, the case is a bit beat-up (it belonged to a touring band in the UK, Space, and so was a bit the worse for wear when I got it). Also sounds-wise, I never use the arranger functions and the soundset is outclassed by the Roland XV.
I was going to buy an OASYS (the PC-in-a-shell, not the SHARC based device) until I learned more about them. Also, same thing as the Trinity - I don't need the arranger functions. I have a Mac with Cubase.
Now it could be that I'm fussy or very specific. But what I want is:
A graded (think KX8 or Korg's RH3 mechanism) hammer action piano-weighted 88-key keyboard.
A new synthesis source.
Space is tight; I don't want a module and controller - I want an instrument I can just play and is self-contained, but whilst I'm not a trained pianist, I've been using proper weighted controllers for almost a decade and I have this hope that the continued familiarity will allow me to play proper piano when I have the inclination and time. I want the muscle-memory to understand that "this is what a keyboard feels like".
As it stands, John's prepared to make it happen if I'm prepared to pay for it, and the costs only slightly exceed a new OASYS, but that's still a lot.
In terms of product justification:
People who buy high-end synthesizers usually like a wide sonic palette and probably also use piano sounds. However, most weighted devices are either arranger-keyboards with balls like the M3, OASYS, Motif etc. - or they're dedicated stage pianos with a long shelf life. The K2600 is very good, but it's 1992 very good under the hood.
I can upgrade my piano sounds to the latest and best using constantly evolving computer technology. It really is "sample and synthesis" at the core and that's something that gets left behind quickly - look at Roland's JV family, you've got a new - and still imperfect - piano every 2 or 3 years from them.
But a synthesizer - that's something else. Once the technique for synthesis is established it remains "useful". So a long-lived keybed and a long-lived sound source? Ideal.
This is deliberately overlooking the fact that John's past work was looking at some devices which ultimately evolved into exceptional modeling capabilities and I've no doubt that the Solaris character could be "changed" to provide a killer piano with all those DSPs

So. What would you think of an 88-key, weighted Solaris? Would you pay a premium for it (the typical premium for 88 over 61 keys is between £700 and £1000, but smaller runs=larger overhead I am assuming). Would you be happy with "A Solaris with more keys", or would you only be interested if there were more controllers or similar (I don't want more, though I thought it would leave room for a larger ribbon). Would you want clever mechanical engineering or be happy with an essentially featureless extra area, just a wider synth? I personally use the empty areas on my Trinity as a surface for controllers and interfaces, so I like empty space.
What I want is nothing more than a wider Solaris. No extra features or interfaces beyond the keyboard. Width could even be saved by moving the wheels from beside the keyboard, to above it alongside the joystick.
If anyone else wanted such a thing, then there's a possibility it could happen.
(Just to clarify, my reluctance to go with Korg's current OASYS has a lot to do with how they implemented it and the impression I get of their ability to support it long term from their forums. I think the product - as a finished object in front of you and playing it in isolation - is stunning. I'm just disappointed that for the money, it's all software, no DSPs, no "cleverness", just 6 year old PC technology in a nice shell - the lack of evolution means I'm really reluctant to go for it on a value basis).