The MoYu AoSu 4x4 is the 2nd 4x4 in the MoYu series, which has been responsible for some of the most popular cubes of 2013. The AoSu features adjustments in design over the WeiSu that are intended to improve corner cutting and overall performance. It is also feels a bit lighter and scratchier out of the box compared to the WeiSu.