The only time I liked my ( chipped ) X5 3.0d has been at the gas station from time to time. Due to the narrow rpm range available you have to shift more often compared to a petrol engine ( the steptronic does this for you ). No top-end power, no engine sound, no higher rpm's. No fun. A diesel makes sense in a big and heavy car like a SUV/SAV. Not in a 335.
My 2 cents.
Not more than 500 chp for my daily driver. Well, ...