My own Zetec estate 2.0 TDCI is just over 3 years old and 37K miles up. It's needed one brake light bulb, a set of rear brake pads, a pair of front tyres and annual servicing in that time.

A higher annual mileage is likely to be better for the car as it implies more motorway trips = optimum running conditions.

The cambelt service is 8 years / 96K miles so you've got a while before that needs attention.

I've had no problems with the DPF, the Ford system seems robust and unlike some other manufacturers' implementations, doesn't have a 'traffic light' system to tell you that you need to go for a regeneration drive.

My simple rule is, if a regeneration is taking place (you'll know because the engine cooling fan will come on and the engine note will be a bit 'boomy'), just drive around the block until the fan switches off. Only takes a couple of minutes.