Hi all, I am looking for a good walking lens for my Nikon D60. Unfortunately I don't have a lot of money to spend but I also don't want to get a lens that isn't very good. Is the Nikon 18-200mm VR lens worth the money? Am I better off saving the money and grabbing a similar range Sigma or Tamron lens? Do you recommend any other brands? I am not a professional as you can probably tell by my question so I am not sure if I would notice the difference between the results of the different lenses. What do you think? Thanks!