This may seem like a strictly personal dilemma, but I'm looking for opinions to help me decide because I haven't been able to come to a conclusion. I currently own a Sigma 10-20, Nikon 50 1.8, and Nikon 55-200. I had the kit 18-55 that came with my D40X, but I ended up selling it with the body. Now I find myself without what seems to be a primary lens for many. I just purchased the 10-20 a month ago, but with the arrival of my new daughter I am beginning to wonder if I should have invested in a good 2.8 normal zoom. I do love to shoot landscape, and love having wide angle, but I wonder if a 17-18mm on the short end of a normal zoom would serve me well for most purposes. When I think about selling the sigma, I wonder if having a normal zoom will really be worth losing wide angle, considering the other two lenses I have. Granted the 55-200 isn't of amazing quality, and the 50mm is prime, so I would have a high quality zoom in a shorter lens, but I just can't say for sure what would be the better option. Switching around $500 like I change my underwear (don't worry I change them more often than monthly) isn't something I want to do unless I know it's for good. Could anyone share some thoughts on this? I realize to some this may be chump change, but it's a hefty decision for my pocketbook, otherwise I'd have both! Thanks!