I think he can be very useful when on song.
I don't personally have the strong love for Feki that some people do, he has been impressive in the back end of the year but i also believe he's prone to big handling errors both in the air and ball security.
In saying that i'm with CB4., i can't possibly see how you can take him off the field for Barba. Feki's great strengths of getting us out of our own end and getting us on the front foot in our sets is invaluable and particularly because of the nature of the gameplans we bring.
If Barba is on the field, it has to be at the expense of Gordon. At present - you wouldn't do it because Gordon has been pretty damn good.
Very difficult situation for Flanno and he will be either hailed or crucified on it.