I'm not sure what unstable means to you. But to me, the Meilong is a little unstable because it is "loose"—you can easily slide and distort the cube by pressing on one hand and turns too easily. This doesn't happen with the MF3RS3 or the YLM because both have deeper stalks inside.Yes, but the ylm would be a little unstable, would you recommend the RS2 over the YLM?
On the other hand, YLM is very quiet and turns smoothly OOTB without lube. MF3RS3 is has a bit of spring noise and feels "sandy". IMHO, RS3 requires some lube.
Lastly, YLM and Meilong are low budget cubes. So their plastic feels cheaper and are frosted. MF3RS3 plastic is of higher quality gloss and feels smoother. Just so you know if "material" bothers you as well.
