Hey guys I have some cash now, and want alot of things. http://www.adorama.com/SG5028DNKAF.html So I am want the most for my money, and was looking into purchasing a macro lens, and when I heard this is very good for landscape I fell in love. I only shoot macro and landscape pretty much, so the lens itself seems to be perfect, price range is perfect. But my question is, how much of a upgrade is this over the stock nikon d40 lens? What would the quality difference be build wise, investment wise, performance, and whatever else you can think of. Help appreciated.