DPF on a CR 2.0 TDi I hear you mutter, I have a 58 plate A4 B8 TDi 143. I got this car 0n 21st September 2008 and today it has clocked 59,000 miles, it has had three dealer services and has also had two dealer visits for DPF Issues!
When I first got the car I noticed after 18,000 miles the engine would idle at 1,000 rpm and drive very well, throttle response was excellent, I later found this to be the DPF doing a regeneration so I now know what this is, so I drive at 60 mph in 4th gear at anything above 2500 rpm, after 5 or 10 minutes the regen is done and the car sets itself back to normal.
The other issue I had again DPF was the car started to do as described above but after 30 seconds the emissions workshop lit up on the dash and the glow plug light started to flash indicating the car was in reduced output mode, when Audi assist arrived he put the computer on and the error was 41.3 grams of soot on the DPF sensor, safe level for forced regen 40 grams, however he would not force a regen and my car spent two days in Audi for a new pressure sensor in the DPF.
I use BP Ultimate or Shell V power diesel and cover a lot of miles, I think most of the problems above are down to new technology just needing the niggles ironing out, if you know when the car is regenerating and you can go for a quick high revving spin up the motorway you will have no issues.
J