Just my 2 cents...
I have wanted one of these for almost 6 years (but had to save), in that time i have owned a Fiesta ST (i know!), Audi A3 2. TDI, 1 and 5 series BMW as company cars.
The GTI is the best car I have driven out of the above. Hands down. Finally got enough saved to buy one and ditched the company car.
Granted the fuel (V POWER) does cost that little bit more, servicing may be a little bit more, but I will be keeping this car for a very long time.
A very worthy upgrade from your Focus, indeed.