I didn't believe this could possibly work, but was staggered that five minutes after I'd installed this brilliant plug-in, I had an IDENTICAL, fully-functioning site on a different domain.
I thought I would come unstuck as obviously I had to install the latest version of WordPress (3.9.1) whereas the original site is 3.1.2, but here's what happened: I installed WP Clone on the new WordPress site, clicked 'Restore Backup' and pasted in the backup URL. Momentarily, I had the older version of WordPress of course. Having checked that everything was fully functional I then upgraded WordPress, safe in the knowledge that I could always 'Restore Backup' again. That's when I expected things to go wrong, but no, everything was hunky dory.
I'm gobsmacked and delighted at the hours and hours of work the WP Cone has saved me, and I can't say enough good things about it.