It's the best 6x6 you can buy with €20 and it is magnetic which is vital in big cubes. The customer service was also very helpful and quick to respond. This is the cheapest place to get wca cubes in Ireland.

not only my first 6x6 but also my first YJ branded cube,
what an amazing difference, good strong magnets, love the glossy texture,
well worth the extra few €€€

So I have the YJ MGC(€21.60) and the YJ Yushi(€13.60), and I'd say they are tied for best 6x6(*if they are set up properly*).
The Yushi is equally fast on all layers, while the MGC has awesome, faster outer and second layers, but the middle are a little slower.
The MGC pops... not too much, maybe once per ao25,(it is easy to push the pieces back into place) but the Yushi has popped once ever, and that's out of 200+ solves.
After 3 weeks with the MGC, all my PBs are mixed between the two cubes, but I did shave 15 seconds off my single and 8 seconds off my ao5.
The MGC definitely feels more premium, and like it has more potential, but the semi-frequent lockups and pops bring it down.
OOTB, the Yushi has a weird squeak and spring noise, but lubing the core fixes these and makes it faster.

Overall I would recommend the MGC as it takes significantly less setup and break in, and is a hair faster, even if you are just getting into 6x6.