We were purchasing a BMW while working abroad for the UK government. BMW were able to offer GBP based pricing whereas at the time Mercedes could only base of Euros, which proved significantly more costly.
Though my model (23i - does not appear on this site yet) is the smallest of the three, it still packs enough punch for me. Again more of a tourer than a true racing machine. An excellent balance of power and smoothness. More money I would choose the 30i
