They seem to be selling quite well.
Especially now you can pick one up for 265 euro's.
Sure if hey would have gotten the price right from the get go it would have been good for sales, but I hardly doubt they're lying awake at night. Even if it's not the massive succes it could have been they're enabling a lot of musicians to get started with electronic musician for cheap and experience the far superior build quality of the Refaces compared to some other major brands (Looking at you, Roland, the JD-Xi's are losing keys like they're hairs).
I for one will first look at Yamaha when looking for a second synth.

Well They started out at $799 or $899 USD.
And that was a total bust.
Yes, they are priced correctly Now. But Will Yamaha keep making them???
OR
Are we just Seeing Yamaha recoup their investment. Then Discontinue?
That Is What concerns me. I love the Little 1 I have. And I want The Piano one too. But do not have room for all the hookups and....
Really would like a full size one. Containing All the models in 1 unit.
And yes. people are getting a good deal on them right now. But 4 how long?
Japanese companies.(Culture Thing.) Tend to. Never revisit. What they consider a failure. And believe me. They consider the Reface a Failure.
$799 down to $250 for the CS. Was never in their plans.

One last item on this.
Whatever they do. They cannot combine all models into the same size Keyboard. Then it still looks like a MINI.
The MINI(Ipad market). Is pretty well Cast in stone. As below $500. USD. So that would cause the same pricing problem.(Although personally. I would like it.).
But I am sort of the same mindset. I Doubt I would Pay over $500 for it. Again Perception is everything.
My Montage. Looks and feels like a Expensive piece. And I have never had price regret about it

Well They started out at $799 or $899 USD.

That was MSRP. Street price was maybe $499 when they came out. (My wife bought me a YC not long after they came out, and then a CP for Christmas that year. I love them both, but I'm more an organ guy than a piano person. That said, I would've preferred an acoustic piano rather than the Toy Piano.)

Japanese companies.(Culture Thing.) Tend to. Never revisit. What they consider a failure.

Truth be told, I would never have expected them to revisit the YC series some 45 years after introducing them (and probably over 35 since the discontinued them).

$799 down to $250 for the CS. Was never in their plans.

Except it was never $799 as a street price; street was $499. These days, MSRP looks like it's $699, with the cheapest I'm finding it being maybe $286 new. Same for the DX. But the YC and CP seem to be going for almost a hundred dollars more.

I'm no Yamaha apologist...I certainly would've done some things differently with this series. Nor will I judge whether it's a failure or not. I don't have the sales figures or access to their hopes for it.

.
Really would like a full size one. Containing All the models in 1 unit.

I agree 100%. And if you look through these forums, you'll find a few of us who've written something similar. A "Reface Pro" would be great. I'd even be OK with them making the 4-model version the upper end and just combining the YC and CP together and the CS and DX in a separate unit, just charging a bit less for those, since they'd have less functionality.

However, I have seen no indication that Yamaha has any interest in doing this. I'll admit, however, that I've kind of lost hope in this and stopped checking in here much.

Combining several soundengines in one keyboard is one thing, this is something that has been done before by Yamaha and other manufacturers.
But the 4 Reface models have 4 different user-interface surfaces. The DX has a menu-driven interface with 4 virtual sliders, the CS has buttons and sliders for every parameter, the YC interface has drawbars that organ players are familiar with, the CP has a limited number of controls to select presets and effects. Combining all that in one keyboard withot sacrificing the model-specific fun of the individual models will be difficult.

If I want a full-size, pro level synth, and decide it has to be a Yamaha, I would buy a Montage.

Combining several soundengines in one keyboard is one thing, this is something that has been done before by Yamaha and other manufacturers.
But the 4 Reface models have 4 different user-interface surfaces. The DX has a menu-driven interface with 4 virtual sliders, the CS has buttons and sliders for every parameter, the YC interface has drawbars that organ players are familiar with, the CP has a limited number of controls to select presets and effects. Combining all that in one keyboard withot sacrificing the model-specific fun of the individual models will be difficult.

I'm not really a synth guy. All I want is the YC and the CP put together into one. If someone wants to hand me a synth section, too, that's just icing on the cake. Personally, I'm more in favor of two separate Reface Pro products: Full size, of course, but putting the YC and CP together would be quite easy and handle most of the needs of someone into vintage organs and electric pianos (and, hopefully, an acoustic piano or two). Remember, Nord has them (and a third section, as well!) in the Electro. And yes, the more recent Electros have actual drawbars. Hell, Korg has their virtual drawbar thing in the new Continental. A Reface Pro - even with only 61 full-size keys - would have plenty of room for the controls of the YC and CP. How am I sure of this? Well, I currently have both my YC and CP sitting side by side about a foot above my Novation 61 SL MK II controller. And together, their width is less than that of the Novation. Now remember that if it's a piece of Pro gear, you probably don't need any of the speakers that the Reface currently has built in. Now you have room to choose between making the controls bigger, adding others, or leaving extra space. Really, chances are that you could also combine a few of the effects...like reverb.
[And yes, you could put the DX and CP together in another full size unit, keeping their same controls.]

If I want a full-size, pro level synth, and decide it has to be a Yamaha, I would buy a Montage.

Well, firstly, what most people seem to be talking about here is something in the sub-$1000 range. The Montage is a few times that cost. So you're not comparing apples to apples. Furthermore, the Montage costs so much more because of the functionality it has. But that's not the functionality that many of us need (or want). Like I said, I'm not a synth guy. I'd be perfectly happy with a product with 61 full-size keys (or 73) that gave me the organ sounds (Yamaha YC, Ace Tone, Farfisa, Vox and Hammond) that the Reface YC has, plus a slightly modified version of the CP. (I'd be satisfied with Rhodes 1 and substitute a Pianet N for the Rhodes 2, then substitute an acoustic piano for the Toy Piano). Your needs are different. But remember that people bought the Reface YC and CP because they wanted those sounds built in. They didn't want to be loading libraries, assigning parameters and functions, etc. Just move the knobs, etc. and you're there. Much like they did with the vintage keys they were honoring.

I can see your point.

If I want a full-size, pro level synth, and decide it has to be a Yamaha, I would buy a Montage.

Perhaps Montage successor will combine Reface engines, Montage engine all in the same board...