Just recently took notice of the extensive ewrc-results.com data on rally cars and drivers (amazing work from all those ewrc guys!).

These particular data suprise me: Kajto used 5 different R5 Fiesta's on his 8 2015 ERC rallys; 4 of them were brand new, the other was almost new (with only 1 WRC2 previous event). Breen used 3 208T16 units on his 9 2015 ERC rallys; 2 were almost new (1 WRC2 event and 1 '14 ERC rally each) the other was a used one (with a full '14ERC season).
http://www.ewrc-results.com/profile.php?p=4113
http://www.ewrc-results.com/profile.php?p=5636

Of course it was Kajto amazing driving, with a perfect balance between speed and consistency, that made the main difference, but these material availability helps to understand the Fiesta superior reliability and how, sometimes, factory teams are only factory teams...on name.