At 48x, my Nikon Prostaff 16-48x65 can crisply focus the period at the end of a sentence in standard newsprint at something like 12 feet from the objective. Honestly, I'd trust the close-focus specs (for name brands, anyway) since it is so easy to check/verify. As I understand it, Nikon has a camera adapter but I don't know anything about it.
I agree with EsoxLucius, try them out before you make the purchase. Even though you usually get what you pay for in optics, higher prices don't always equate to better quality. The Sightron scopes I looked through were no where near as good as the Nikon, and were considerably more expensive. On the other hand, the cheaper Bushnell scopes were, well, cheaper... Stokes and Vortex either weren't around or for whatever reason weren't on my radar when I was researching spotting scopes, so I don't know anything about them.
Good luck!
Just a Shooter