they are lovely cars and greatly underestimated imo. the bf has a b4 gtb as daily and its very very comfy, not bad on juice, very fast (ok, its modified) and practical. handle very very well as they have a long wheel base and are well balanced. i would recommend 4pot brakes (they bolt right on and those wheels will clear them too) because the stock 2pot brakes are simply lethal!
as far as economy goes, the bf's has an a/m ecu and i managed to get 38mpg out of it one day.
they are not bad on fuel imo depending on your driving. but hey, if its crazy economy our after, get a tdi lol