It's always kind of luck of the draw when receiving any new knife on how good the action is in my experience. Even high end expensive folders. My iMamba is the only one I've ever handled so I can't speak on how they are in general, but mine is literally like perfect. The detent, lockbar pressure, bearing action are all tuned just right and somehow work equally well for thumb-rolling, flipping, and spydie-flicking. It is a little bit different than the majority of knives out there with anything but flipping because of the fuller/notch/nail nick being a little bit further from the end of the scales than normal but it works really well in my case. Possibly it would smooth things out if you took her apart, cleaned everything real well and then applied just a touch of whatever oil you use. Be aware of the loose ball bearings though.