The point is that lot of european people like diesels, and is220 is more economical than the 250. Yes, its not the worlds best diesel, but it does its job well.
I can cover about 700+ km in full tank in my 220, with 250 you will be able to cover only half of that. In one year you can save a lot of money.
And is220 IS QUIET. It runs very smoothly and quiet. I dont know if its luck on just well serviced car, but i havent had any major issues.
I will never go back to bmw, audi or a merc.
If you are a diesel hater then there is nothing to talk about it anymore.