I can reset my MPG display and drive with a light foot on parts of the motorway and see 30 mph + displayed but as soon as you leave stop/start/big hill etc its ruined. Best I can get driving normally on a long trip is a genuine 25 mpg out of the TDV8.

04 td6 does 24mpg on my round trip to work, 13 miles each way, mix of town and dual carriageway. I checked tank to tank and the computer is surprisingly accurate.
The only way i can get it to say over 30 is by resetting mpg one the engine is warm.

For servicing, parts for an oil service and filters come to 80 quid or so. Easy to do yourself if you've got a big enough bowl to catch 9 litres of dirty oil and a bit of determination when you do the air filter!

Budget on replacing some part of the b#@!*$y suspension each month too. :/

I think the performance is adequate. More than enough to keep up with Lane 3 on the Motorway (if you can afford the fuel). It can shift off the line of you really hoof it as well. I wouldn't call it 'fast' though and if you're racing for a space in traffic the size of the thing makes up for any lack of pace!