This cube is pretty neat.

Okay, yea, there's practically zero corner cutting and it locks up every 5 moves or whatever, but that's beside the point.
The point of this cube is to be interesting to look at and solve, and it's not supposed to be a speedcube. It has a clicky mechanism which can be kinda annoying, but again, it's not for speedcubing.
It's about the size of a regular 5x5, so it's not too terribly big for the mechanism.
Also, yea. if you turn the middle slice 45 degrees, since the cubies are different sizes, it'll allow you to turn the L or R slices, making the centers switch places with the edges. It doesn't shape shift the corners, though.
There are only 3 different types of parity with this, one being the centers can be switched around once you get it back to cubic shape, one of the edges not facing up on the last layer, and 2 of the edges switched around in the last layer.
All in all, it's a fun cube to get after you know how to solve a 3x3 because it adds a little extra difficulty. The only thing keeping this from a 5 star is the turning, but I can't blame WitEden or Oscar because of that. Have Fun!

I don't have one (yet), but this is rather amazing. See Oskar's YT videos about it. Glad to see a trustworthy domestic source for it.

For the rare bird who is interested in mechanisms, this is reputed to be extremely difficult to reassemble. I had no significant trouble with a V Cube 7, fwiw.

Just possible that it's costly because it's not easy for the factory to assemble, either.

This puzzle takes getting used to, turning-wise. When I first started playing with it I felt disappointed and concerned about the quality but as I solved it, it became clear it just needed to be broken in - after about ten solves the puzzle feels DRAMATICALLY better. The mechanism makes for a feeling I've never felt on another puzzle; not either a bad or good thing, just unique. Doing algorithms sometimes requires slight patience as there is the occasional lockup but nothing too crazy.

I'm always wary about purchasing uniquely turning puzzles because their enjoyment may be hindered by their turning. This however, after some breaking in, turns amazingly.

Build:
What makes a mixup cube special is that the edge and center pieces are interchangeable via rotating the middle slice 45 degrees.
The 3x3 mixup shares almost the exact same internals as the 4x4 mixup, using edge and center caps to bandage them together. Although I have never encountered a pop, I know from disassembly that this is a tricky puzzle to put back together. If this puzzle were to pop, you should be able to feel it coming via a snag.
Avoid removing center caps, as they are very easy to bend and disform.

Turning:
Out of the box, this puzzle's turning will be very rough and feel like it is constantly snagging; I suspect in-part due to the 4x4-internals. After a couple break in solves, however, these issues have mostly gone away, only leaving behind the occasional snag.
The turning can of course be further improved by adding a couple drops of lube and working it in. I find the easiest way to get into the internals is to rotate a middle slice, and pull at an edge cap from its un-stickered sides.

Stickers:
On my 3x3, sticker placement was fine. On my 4x4, however, some stickers were off-center to a point where they scraped against other pieces, so your mileage may vary.

Below is a turning demonstration, as well as comparison between the 3x3 and 4x4 builds.

This cube is very fun to solve, the only issue I have is that the picture shows a regular Orange/Red Blue/Green White/Yellow color scheme where as the one I got was Purple/Pink Blue/Green Grey/Bone. Other than that it's great.

My first mixup had massive turning problems, thanks to the cubicle support for the quick help!
The turning still isn't perfect, but it's acceptable. Just be aware that you need to be a bit careful with turning, there is a lot of internal pieces. It's not a speedcube, there will be some catching.
That's the only gripe though, it seems sturdy and it certainly is unique, and therefore a recommendation from me!

I am very happy with this cube, as far as twisty puzzles go, but it does get annoying sometimes because this puzzle has a lot of hidden inner pieces in the mechanism, and if they are not lined up just right it will be very hard or impossible to turn a layer without getting that lined up first. Right now the puzzle takes me around 3 or 4 minutes to solve, so overall it is really fun!

Fully functioning shape shifting mixup cube! But..
-bad turning, the cube sticks aot and gives you the feeling it might break if you work too fast.
-stickers - my cube was stickered bad with blue & yellow stickers mistakenly swapped. It drives me crazy!! Low quality of stickers..

Witeden mixup and camouflage are some of my favorite cubes. This particular puzzle turns very good (I’m not corner cutting this to or speed solving just to point out), stickers look great, and has a parity I haven’t wrapped my head around but is a welcome challenge!

To say the best, this cube can be OK. It cannot corner cut, and it locks and pops almost every turn. I find that superglueing the little pieces inside decreases the popping alot. I don't know why they didn't make it conjoined in the first place.