how to respond when asked "why don't you get a DSLR?"

Just thought of a simpler answer.

Just say that the DSLR is like a Nikon F and the NEX is like a Leica M. That doesn't do justice to the versatility of the NEX but most people with even a vague knowledge of cameras will understand.

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- -Better a small camera in the pocket than a big one on the shelf --
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