ive driven the 3 series and the merc c,
the 3 series and its a good car with a sweet motor and it handles beautifully,but it looks kinda stupid from the back and it has very less leg room which you would expect more from a beemer!
though the merc looks much better than the beemer,the ride isnt as enjoyable(handling) as the beemer,but i would say very very close.very nice car aswell.but i kinda liked the merc for no reason,
and the audi just looks FAB!the best looking car out of the lot,and the base model has alot of options comparing to the beemer,
so if i were you,Id go for the MERC,but yet again,i was just being me,i wouldnt blame anyone for choosing the other two as all of these cars are brilliant!