Originally posted by Sol Invictus It's a fantastic lens. Great IQ and blazing fast AF. However if you want to save money, the new Tamron 24-70 is an excellent choice. One notch below the Nikon, but you save hundreds
I don't have the Tamron, but do have or have used and since gotten rid of the following...
Got rid of the Pentax 16-50, yet still borrow a friends... I'm one of the MANY whom have experienced numerous issues with that lens, both focusing and also zoom lock. So if you do happen to choose the 16-50; always try to have a spare lens available.
The Nikon 24-70 is one of the best zoom lenses on the market; there's not much that is better.
On a side note, the Sigma 24-70 f2.8 is darn close, still full frame, and also in most categories above the Pentax 16-50