I will speak for myself when I say that given the price of the product and its market, I am generally very satisfied. Nothing is lacking, and everything is done well. This is my first DSLR. I compared the D90 with the noise, and the D90 comes up short! The D3100 Expeed 2 matrix is the same in both 5100 and 7000. Hence, there won't be any change in image quality between the D3100-D7000 price range; instead, the 7000 may have less noise and the added functionalities. Take full-frame right away if you decide you've outgrown this device or if you simply want something better and different. Because switching from one crop to another is not a very profitable endeavor. I just purchased a 50mm 1.4 lens, and as I'm getting used to it, the picture is drastically different! By the way, the whale 18-55 lens is not a bad one; considering its cost, it performs admirably.)
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