fwiw, there's a local rando who did last year's 750-mile PBP on a french alex singer from the 70's (with a gigantic handlebar bag on it) - in 50 hours.

take a look at the PBP 07 results here, and you'll see that most times are in the 80-90 hour range.

(ok, granted he might have paid more than $2,500 buying and restoring it, but still - it weighs 22 lbs unloaded)

all that said, i like my $2,500 bike.