I am a professional and former Nikon user. As a Nikon user, I have always used Nikon glass exclusively, with the exception of this Tokina. I decided to try this lens on the recommendation of a colleague and read several reviews online. Summary of my review. HOLY COW! This lens is very sharp! The 100mm focal length is not only great for macro shots, but also great for photographing people (see attached images taken with this particular lens). If you've read all the dyno testing information, I have no doubt that the autofocus is a bit slower than Nikon-made lenses, but I assure you, unless you're shooting fast-moving subjects, it's not a problem. I mainly used the lens for model photography (handheld) and the autofocus is more than fast enough. I always thought you get what you pay for, but this lens is cheaper than Nikon glass.