I've had a Moyu AoShi for a few weeks and picked up a ShengShou 6x6 a few days ago. I think they both turn lightly enough to fingertrick but the AoShi cuts corners a lot better and the ShengShou pops like mad. The popping is maddening and makes the ShengShou nearly unusable. It also has an odd issue that on three of the sides, if you do a 2U2 or 3U2, the top layer only does a U or U+U/2.
So far I think the AoShi is far superior but I haven't used either extensively enough to give an authoritative opinion.