Fiesta, all day long! We owned an st170 for about 7 years, 1 previous owner at 15k, we sold it at 76k. It had every single one of the common issues except for the fuel pump but always had it in mind it was a matter of time. My mrs drove it and it's a very expensive car to own pound for pound against performance. Keep it in the revs and through the box it's lively but not record breaking.
Commuting 20miles round every day she would get max 24/26 mpg but could be as low as 19, I get 30 from my Barbarian! It needed a pair of tyres every year for the MOT as it wears the inside edge, the rest of the tyre would have loads left!
I enjoyed driving it for the 5% of the time you could actually use it properly but the rest of the time it had reached the point where the cost of repair and running was too much.

To be honest though. Take off the ford blinkers and drive a type r or consider a Clio 172/182?