I used to own a 1.25 MK6 I think (54 Fiesta Finesse) it was a lovely car, but was a bit gutless, I have driven the MK7 1.25 a few times, and I find its more gutless than the MK6 equivelant! At least I could do a decent wheelspin in my Finesse, but I can barely get it out of the MK7
The Fiesta for me, is a good car, but its let down by the fact that Ford just do not pay attention to the quality, I just feel like Ford have let it down by not spending the extra few quid on the interior quality. The engine being a bit wussy is my personal begrudgement, but then again, I tend to otherwise drive 1.6 onwards, and have never gone back to that sized engine.
They are good cars, dont get me wrong! but they are not my favoured, and I just think you really need to think about what sort of power and comfort you want from it. I would question if you might be better buying yourself either a B Max or a Focus instead (if you want a bit more bang for buck).
I honestly havent driven a 1.4 and to be fair, they may be the saving grace for the disappointments that I see personally, but you have nothing to lose by testing a few out on the road and seeing how you feel in it! some cars just fit and behave like a perfect glove, I found that with the Mondeo, and cant say I ever really saw myself being a Mondeo man! Perhaps there is even a perfect Fiesta for me, just... not below a 1.6 engine