Petrol is fine. Most of the dervs are now utter shite at Euro5 or above. Why would you even pick a derv unless your doing mega miles. I can categorically state that in the last 12 years I've worked in a Ford dealer the only faults Petrols have is lambda sensors and cats when they get to 10 years old Ish. Diesels are lucky to get to there first service before they've broken down or pinged the management light on.