I bought this 166.064 from 1972 about 4 years ago, gifted to my (now) ex, then bf. I felt it always looked too massive on my wrist, although it's only about 36-37mm I think. Must be the large cushion shape of the case. Looks great on his wrist, though. I do get to try it on every so often...
They're good looking watches. A more telling measurement is from 2 to 8 instead of 3 to 9 without crown. This will account for how it wears due to larger surface area on the lugs.