not bad at all. I would be using more in dusk/setting sun/just after sunset conditions, though. (Which would probably work even better than your night example).
I know a wedding photographer who took great reception/dance floor shots with just a SB-700 pointed straight up and using the built in bounce card as the only modifier.. To be honest, I thought it looked even better than your result above. Hmm... The more I look at your picture I am liking it. What is the farthest effective working distance with the flashbender?