I had a D5000 but after 2 years the screen went black and it was a complete disappointment. I didn't want to spend another $600-$700 again, so I went with a cheaper model since it has a lot fewer options. But I've never used all the options of the D5000 and the D3100 has a lot of options to get really good shots. The lens, battery, and accessories were all interchangeable, which helped a lot. The pictures are still beautiful because the same lens is used. If you're not a professional photographer, this works great at no extra cost.
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