Someone talk me out of...

[pdedse]

So, noodling over the NC 750X, Versys 650 and V-Strom 650. All available in my area with decently low mileage. Each well reviewed on the web with their pluses and minuses.

And all called “The best all-rounder you can buy.”

Have you considered the MT-07?  A Moto Guzzi V-7?  A Ducati Scrambler (Nightshift is my favorite)? 

hahaha....I jest.  

I'd wager which ever bike you choose, you'll end up thinking you got "the best all-rounder".  Since they are all good, how about other factors?  Likely, you've already considered: Aesthetics? Do all come with luggage?  Is one easier (harder) to work on?  Does one particular bike have a new set of tires?  Does one brand pull at the heart just a little more than the others, even if it's a few hundred more?  In then end, if you were less than happy with the one you choose, you could sell and try one of the others in a year or two.

Good luck!  Will be fun to see which one you go with--if you do add another--and what you think of it in time.