Hi, I am in a conundrum as to which lens to buy. I would like to replace my rather tired 18-55mm lens. The lens came with my D50 and has become rather floppy. As I am a student on a limited budget, i mostly buy second hand lenses. My local camera shop currently has several lenses that would be a good fit but I'm a little lost on what to get. My current gear is a Nikon D50, 50mm F1.8D, 70-300mm F4.5-5.6G and an 18-55mm F3.5 - 5.6G ED (1) lens. I also have a Nikon extension tube. In the long term I want to get an ultrawide zoom and a new body funds willing Which would be a good investment? AF 35-70mm f2.8D AF-S 18-105mm f3.5-5.6 VR AF 28-105mm f3.5-4.5D They also have a D40 and 18-55mm kit lens for the same price. Any advice would be appreciated?