Hesitating AF is not typically a lens issue - the lens only moves as it's told - the body needs to decide where and when and if it's focused. The autofocus capability depends on the f/number of the lens for the same body, so with an f/4 lens it will autofocus worse than with some f/2.8 one for example.
A really good test of autofocus is to just check it manually - put your camera on a tripod, point to some fixed object (not moving in the wind for example), autofocus on it and then focus the same object manually on liveview on maximal zoom in preview (I assume your camera has such function), compare results. That really shows you whether the AF is good, I found out for one lens that it isn't and even a relatively expensive "backfocus adjustment" did not solve it.