A pro-caliber fast midrange zoom. It's old, it's Tokina, and it's cheap. Does that mean it's not good? Well, as with everything in photography, the answer is: it depends. It depends on your needs, your expectations, and what you're comparing it with.
+ constant f/2.8 aperture makes a difference when you need it.
+ very decent image quality wide-open, well balanced overall. Excellent closed down to f/4 or f/5.6
+ superb construction quality, it can take a beating
- not as reliably great at all apertures/focal lengths as the (much, much more expensive) Nikkor AF-S 24-70 f/2.8
- screw-type autofocus.
- although it's inexpensive, it's still 3 times the value of an AF-D 50mm f/1.8
|In places like a museum, a fast midrange zoom could be useful|
- Walk-around lens for museums
- Concerts in dark clubs (provided you can get near the front)
- Pretty decent wedding lens for the budget-minded
- Entry-level cameras (no autofocus without motorized body)
- DX in general. Any 18-xx zoom is better suited for your needs
- For those who don't mind swapping lenses, a combo made of the primes 35mm & 85mm is far superior in every other way
It's great value, if you need a midrange pro-caliber zoom. It's more than 5 times cheaper than, say, the AF-S 24-70mm f/2.8. Is it 5 times worse? No, it'd be unfair to say that. Surely, the newer AF-S Nikkor is a diamond. Perfectly reliable - flawless, really. But it's really expensive. Consider also whether you truly need a midrange zoom. Like I mentioned above, prime lenses like the AF-D 50mm f/1.8 are optically superior and faster as well. And cheaper. You're missing focal length flexibility - but you should consider what's more important to you: flexibility or absolute quality.