My last-but-one French car, a 1.8 Xantia, managed over 40mpg and was sublimely comfortable.
Reliable too (the wonderfully simple XUD had just been put out to pasture, but this was based on the proven TU engine series).
Unfortunately I was put off a C5, had a bad experience with a 406 HDi, and have had enough horror stories from 307/407 drivers I know to put me off PSA products.
Though comparisons to a Golf? My wife's car has a VW engine, and my co-worker has a Golf with the same engine, they've had issues with ignition coils. The TDis seem to chew through injectors.
The Germans aren't as reliable as their marketing bumpf would have you believe.
A Focus? Apart from a dislike for the fussy detailed turtle-shaped silhouette (they wont sell a saloon car in the UK), I regard Ford with disdain as an accountancy company that throws together vehicles as a sideline (bad experience of a mk5 Escort based Orion, and disgust at the Visteon pension scandal).
So, if I was forced to buy a C segment car, what would it be?
Undoubtedly I'd have a sniff around the gorgeous Mazda 3 saloon (A marque I've always admired from afar but never actually admittedly owned) or a peek at the Volvo V40 (a modern day Saab 900?).