Ford TDCI's can have issues with injectors as you say and the dual mass flywheel can be an issue on higher milages and costs a fair bit to replace, although you can get 'normal' clutches as direct replacements.

Specifically to the Mondeos is rear bushes and rusty doors where the door skins were not sealed properly. Doors should have been done under warranty but I'm sure there are plenty that haven't been.

At that age you could find good or bad with either options but there are plenty about so look around and you'll find a good'un.

hth