I went from 2.5T mondeo (c.28mpg) to 2.2 TDCI Smax (c.38mpg). I preferred the 2.5T to drive, and it was a lot cheaper to buy than the 2.2 TDCI, so I was really happy with it. 2.2 is OK though, I’m starting to like it.
The petrol Smax’s (Ecoboost) are thirsty, and personally, i’d avoid, because, as you pointed out, if your job changes, you might have to sell it, and that is expensive.
Personally, if I were you, I’d go for the 163…the 2.2. is nice, but it’s never goanna be a sports car, so save some dosh and get the 163.
One thing to consider is that the Mondeo 2.5T has better fuel economy than the Focus ST, even though they have the same power output (dunno about the Smax?) so the 2.5T might not be as bad as people think. Really nice engines though.