i used to own a 156 1.9 diesel 150hp went really well ,had it for 3 years and it never missed a beat.The 159's are loads better than the 156 Alfa/Fiat poached one of the top BMW designers to work on the new model! i can tell you now, and i work in the motor industry the 159 is a brilliant car if you can't get a ti have a look at the Lusso speck.Loads of car for the cash they really are cars of beauty.
First one is nice, however I think I'll stay away from the 2.4 engine - seems to be pretty thirsty and suffer from more DPF issues!
Do you do a lot of miles OP?
the dpf is something to watch with a mileage like that. It sounds like you've got your heart set though, so best of luck.
B@