Just test drove a BMW 335d today and loved it! What a rush! I have several reservations though.1)I've heard diesels referred to as "oil burners".If that was ever been true is it true of today's European diesels (BMW,VW,Audi,etc)? 2)Unrelated to oil...is it true that diesel fuel can be problematic in cold weather (New England winters),making them difficult to start? Also,it looks like BMW recommends oil changes every 15K miles.If I pull the trigger here would it be wise to go,say,every 6 months/7.5K miles? TIA!