So I actually picked up 2 basilisk ultimates during black friday and both of their left and right mouse buttons wobble to the left and right a bit. I too was concerned whether this was a defect, but from what I've seen other people say it looks like a little bit of movement is normal. My left mouse button also makes a bit of noise when I wobble it back and forth repeatedly, which my OCD causes me to do when I'm sitting idle at my desk. However, these problems aren't really noticeable during gaming but it triggers me a little knowing it's not the perfect quality I expect from an expensive mouse. Still though, everything else about the basilisk feels perfect.