Definitely recommend front flaps at least. Recently purchased a 54 2.0 TDCI, when inspecting the car I noticed large areas behing the front wheel where the paint had been chipped off and was starting to rust (Garage sorted this). When inspecting the other c-max' on the forecourt, I noticed the same thing.
Initially I wanted a clear film to stick over the paintfor protection, but have been unable to find this anywhere. Prob easy enough to make on your own though.