Been using the Tokina 100mm f2.8 Macro lens since 2.5 years. It is the most used lens in my collection.
in my view below are the Pros and Cons;
Pros:
1.
Tack Sharp right from f2.8
2.
Built like a tank - full metal - will last long
3.
Very affordable - almost 1/3rd of Nikkor's macro and at par with image quality
4. Like the
push-pull for AF/MF ( An interesting fact is, before i purchased this lens i was bit skeptical about the push-pull mechanism for AF/MF selection, I was thinking a switch on the lens would be ideal but now after using this for few years i know how practical it is to switch from MF/AF without even taking your hands of the focus ring. For my Sigma 180, its even worse I have to switch to AF/MF from the camera body and it takes a split second of your time)
Cons: (Not really but good to have)
1. VR/IS/VC - whatever you call !! - not a deal breaker for me but good to have feature and comes in handy at times
2. Extending Barrel during focus - at times, you end up "literally" touching the subject with front element

3. No inbuilt focus motor/Screw drive lns - May be focusing speed could have improved with this option but i am ok since i have a body with motor
4. No weather/dust proofing - I consider this as an important feature since all of my macro shoots are in the field with foggy/dusty environment..
Overall happy with the lens.. can't complain for the price i paid (New lens costed me USD 350, 2.5 years ago)