I need to change my 1 series BMW as I now need something slightly larger and am considering buying a nearly new F30 3 Series. I do less than 10000 miles per year, mainly through my daily 16 mile round trip commute, so think that I would be better off with a petrol model. I've seen many favourable reviews of the 320d diesel but heard very little about the 320i petrol. Is the 320i worth buying or should I go for the 320d anyway? The 328i is likely to be outside my budget.