I recently graduated to the 16-85 VR having used the 18-70 for 7 years. As good as the 18-70 is, the 16-85 is even better as a walk around lens. I wanted the additional reach at both ends, but especially the VR since I do a lot of shooting in the woods handheld where DR can go to extremes from shot to shot.
I bought the Nikon new. The build quality is superior to the 18-70, but am expecting to eventually use the warranty since I made use of it on the 18-70 at 4 years/11 months (had it back in a week).
Also the 16-85 focus required some fine tuning which is easy in a D300 (once you can find & follow the instructions). Also, I didn't want to have to deal with the possibility of having to rechip a 3rd party lens when I upgrade to a new body.