My girlfriend shoots with a D5300 and we do a lot of hiking in the deserts of So Cal, the beaches, a little woods bumming from time to time and so forth and she's never had any problems with her camera. Weather sealing is nice to have, but I swear her sensor stays cleaner than my D7100 sometimes (which IS weather sealed). She's not one for shooting in the rain so I can't go there from experience but Nikon cameras, generally speaking, are pretty tough little gizmos. I don't condone beating the crap out of them, but neither the GF, nor I, have the luxury of treating our camera's like Ming porcelain; they get bumped, scraped and generally rough-housed in the great out of doors on a regular basis and they do so without so much as a hiccup, performance-wise.
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