JGB:
I had no symptoms of BFS *except* buzzing feet, and I went to a neuro and got an "all OK" after nerve conduction study. It went away for a couple of years, or maybe I just got used to it? No, it must have actually gone away, because I didn't notice it again until almost 2 years later, getting tons of bug bites, then swollen glands and twitches, all in the space of 1.5 weeks. Now I have intermittently buzzing feet, plus lots of other BFS symptoms. Lying in bed is when I notice those buzzing/vibrating feet the most. I can actually feel an on/off sensation, like there's a low voltage applied to my feet for a second, alternating with another second's rest.
I can't answer your question as to whether this is unique to BFS, but I can say it sure is COMMON to BFS.
--alyLeoNCali