I have decided to sell my 18-55mm with my D40 body. A few weeks ago, I purchased a D300. I have a 50mm f1.8 and a 70-300 VR. I'd like to get something to "walk around" with that is longer than 55. I have been heavily leaning to the 16-85. I am open to third party lenses but do not know much about them generally (though I have noted some I would like to get). I can't go much above $600 and have eliminated the 18-200 from consideration for other reasons. Any suggestions would be appreciated. Thank you.