i had one of these in 2008 when the ttid first came out, i did 64000 miles in two years. The only two issues i had were a valve fault in the engine which was rectified on later cars and an actuator problem in the turbo (which could happen to any car).
Other than the fact that it is poorly screwed together, i regret swapping it for an Audi A4, so much so, i swapped the Audi for a 93 carrlson, but ended up not being able to afford 26 mpg (at 30000 miles pa) so now have a 3.0d.
Easily tunable, not sure if Hirsch are still going but BSR did a plug n play box taking the car to about 214 bhp.
i found it comfortable and a car easy to drive with little hassle associated with the brand, unlike the Audi. If they were still in business I'd have another, probably the sport wagon in ttid form.