Buying / Common Faults

Hi all,

I'm looking to buy myself a 07-09 plate 2.0 TDI Sport. I currently own a Corolla Compressor and pretty clued up on my Jap/Petrol cars, however the cars costing me a bomb to run doing avg 30mpg on a 60mile commute to work every day. :(

Reason I've chosen a TDI Sport is because obviously it's a diesel so has good MPG but also has a bit more power so seems to be a good choice for my commuting without having too much of a power loss compared to my Corolla. 

Now I'm not really clued up on Audi's or diesels and their common faults so wanted to source some advice before I start my search. All advice is welcome on what I can look out for or even if you feel there's a better choice of car.

Cheers in advance,

Josh.