I am going to opt for the unpopular opinion and would recommend the Jupiter X out of that list 
Versatile, quite easy to learn/navigate and 4 part multitrimbal (5 if you count the drum parts). Great keyboard, fantastic fx and unlimited expansion possibilities. You can also multitrack both audio and midi over usb, which is a big plus for me.
Itās not analog, but my guess is that 95% canāt tell the difference in a blind test, and 99.9% wont be able to tell the difference in a mix.
What is your goal with this synth? Are you running a commercial studio that needs cool gear to impress potential customers? Or do you want something for a private/home studio that will inspire you? Or something else entirely?
I have owned a Prologue and currently own a Fantom 7 and a Montage 6.
I have also played my sonās Quantum Mk 1 and Matrixbrute.
For me the Montage is definitely the best synth.
Another vote for the PolyBrute 12 if youāre looking for a real flagship synth.
Those UDO synths have the nicest build quality ive ever touched. Itās like a military metal enclosure (in blue or white!) with the firmest clicky knobs, almost like knobs on a high end kitchen appliance or something. And yeah they sound insane.
The Moog Muse is neat and sorta affordable compared to others.
I had the Novation Peak for a while, which is the smaller desktop module version of the Summit. It was good - had a very clean sound, and was flexible. But I got a bit bored of it over the years and ended up offloading it. It has a very pristine and crystalline sound. Itās got a few key parameters hidden in menus, although most of the controls are on the front.
The Hydrasynth is a lot more affordable and it sounds fricking amazing, but IMO its quite an ugly design.
How do you feel about the UDO Super 6? Iāve been going through these past weeks and making about a bank of patches a week and have been liking the range sounds Iāve been getting out of it.
I also have an OB-6 but havenāt got a chance to go through and make my own patches yet, so I donāt really have an idea of what kind of range it has. Really digging the patches that the guy I bought it from left on it thoā¦
Thatās the last thing Iād say about Jupiter XM. Yes, the sound is awesome. But even the most basic things like loading and saving a patch are so unnecessarily obtuse that I regularly lost patches even after several months of owning it. Iād recommend this if the UI was better and you love your classic Roland sounds, but definitely try it before you buy it.
The UDO Super Gemini would definitely be my pick, I just think it has the best sound of all of them, though that new Moog might be a close second.
I get where you are coming from. Yet, there is a substantial difference between the X (the one I am referring to) and the Xm. Still, Roland gonna be Roland. But honestly, I find it quite intuitive to work with (and I donāt even own one myself)
Other than faders, whatās different?
Well, not sure about the exact amount of dedicated buttons (donāt own them, but played quite a lot), but I thought there were quite a few more dedicated controls on the X (e.g. for both envelopes) and the faders make a big difference to me.
Also, I happily sacrifice some direct access to get all these Roland classics in one machine, but I realize I am in the minority 
Montage M8X is the one out of the OPs list that Iāve been thinking about.
It would be be an instant upgrade over any of my current keyboards as a centerpiece machine. 88 keys to cover a wide range of pitches, with poly aftertouch, ribbon controller, etc. Better sampled pianos than any of my current machines. Ridiculous polyphony. The onboard sequencers have been criticized but they look good enough for sketching out songs.
The onboard FM-X and VA sounds seem decent enough to me but Iād probably spend more time playing the thing than diving into sound design. I have a modest analog synth collection I can turn to if i want that kind of sound so Iām not picky about the VA engine.
However, this is based on my own tastes and considerations as to how the new piece would fit with the gear I already have. OP may have completely different tastes, priorities, etc.
just get an op-1. its the preferred option for many users of this forum
3rd wave groove synthesiser
richest sounding thing on the planet
3rd wave comes in blue
Iāve had (together with my brother) 50+ synth/sampler models over the years - in 8 cases weāve had/have more than one unit at the same time.
The Sequential Prophet X is, for us, the best of them all (weāve got 2).
I know itās not being made anymore but if you can find one 2nd hand for a decent price, I would encourage you to consider it 
.
Osmose is particular, very different.
Some donāt like it, other find itās a game changer.
I am not looking to impress anyone. I mostly mix in the boxā¦
My studio is 90% private, with the odd job to help out local bands
Those things look n ice. I saw a review a little while ago and liked what I saw
I do believe, if you have money to spend, that a Moog Muse is money well spent ^^
I know I would go for it if I had the money.