Here's a good example of the price differential between the two engine variants and CC versus Emissions tax (€6k!)

http://www.carzone.ie/used-cars/bmw/3-series/used-2007-bmw-3-series-325i-m-spo-dublin-fpa-111814175140167600

http://www.carzone.ie/used-cars/bmw/3-series/used-2008-bmw-3-series-325i-m-spo-dublin-fpa-119514187311406460