After having it for a few days, and having just received my N12, I can add a few things. The vibration I experienced can most likely be attributed to a bad throw on my part. While it’s a problem I no longer experienced on my Duncan Imperial, Butterflies are quite different beasts.
The yoyo does have a problem, however. The problem being its bearing, or the bearing socket; the former being mostly likely after having tried to put it on my N12.
The problem may only be a defect; a poorly molded bearing/socket that causes the bearing to embed itself into the one socket in particular, making it so hard to remove, I most likely morphed the bearing doing so. It spins only a fraction of the time of my newly acquired stock-8-ball bearing that comes with the n12.
Had I not opened it, it may have been fine, but taking apart a yoyo seems inevitable, and this problem should be considered before making a purchase.
I am not really apt to review a yoyo, so for now, here are some pictures and observations. If I was to be fancy, I’d say the shape looks like a double Wing design over an organic-to-H shape. The yoyo has some vibe in it, but it can be fixed by walking the dog. Stupidly, I didn’t try it before taking it apart for photographs, and I had to forcefully take the bearing out, so I may be responsible for its current performance. The two halves have similar weights, so for a cheap yoyo, I’m either very lucky or quality control is decent. The String I’ve received is also not amazing, and was frayed in two places out of the box.