I love the Poly Evolver Keyboard just the way it is. It's the most gorgeous synthesizer I've ever seen.
It does have a Polysix/OB-8 vibe to it.
That being said, the biggest thing holding me back from purchasing a Poly Evolver is a) just one won't have enough voices for me, and b) the price on the used market for even the rack is pretty high. I'd happily pay more for a new synth with a similar architecture and VS capabilities.
Yes, indeed; those are the undeniable disadvantages of a Poly Evolver Keyboard. An eight-voice Evolver configuration will cost you about five thousand dollars these days, and by modern standards, that's unacceptable. But from the perspective of one who's past all that, the PEK is a irreplaceable synthesizer and - in all its biting, hissing, aliasing hybrid glory - just brimming with personality. And that's coming from a guy with very conservative traditional musical taste.
An Evolver is not for the person who wants a standard work horse/work station type synthesizer, or a modern technological achievement with endless features. And it can't substitute for a Prophet 12, nor vise versa. An Evolver is for the person who wants an Evolver. It's a musical world unto itself. Pardon what sounds like hyperbole, but to me, the PEK is up there with the Minimoog Model D. And look at all the shortcomings of a Minimoog! Nevertheless, each instrument is a classic.
I have no doubt that one day the Poly Evolver Keyboard will be a most coveted instrument. Despite all the usual arguments against it, the PEK is an instrument Sequential should revisit.