Mine was high twenties (town) to high thirties (motorway). Excellent cars if bought carefully. I sold mine at 7 years old to my Dad and it still runs like a dream now its 12 years old (regular specialist maintenance is the key).
My Brother has a 1997 318is, so a slightly newer engine. He just recorded 31mpg in mixed driving. He does use all the revs though It does mid 30s on a 80mph motorway run.
It does mid 30s on a 80mph motorway run.