WW Patts?

Hi I am looking to buy a Diesel VW Patt around the 03/04 Reg (UK) i have read reviews on the car and they have all been very good however i have a querie which is even though they are about 4 years old maximum they are all high milers averaging around the 150 mark my question is should i be wary of them or is this fine for a car such as this