I concur with the sentiments here. Ive got an early Mk2 Focus on a March 05 plate, and it is surprisingly solid, doesn't rattle, feels reasonably well put together if quite crude in places. I looked at a few Mk2.5 models when looking for my one, and the interior and fabrics felt cheaper, and the lighter grey lower dashboard plastics definitely feel a bit more grim. Ive heard the facelift is quieter and has more sound deadening, but the interior seems to have been cheapened from my experience. Don't get me wrong, the interior of my car is not the last word in quality, but for a nearly 18 year old car it's sturdy, inoffensive; and for a car that's main use has been that of a van, held up pretty well.
Getting into a friends mk4 Focus, quality was not great. The doors are very light (I suppose this is a fuel efficiency thing, and I know weight doesn't equal safety etc.) the fabrics downright cheap, and the plastics did not feel particularly well put together or high quality. Its a shame as I am now quite fond of the Focus, but the quality has definitely taken a dive. I have experience of sitting in a Focus Vignale in a car supermarket, and Jesus that was nasty. Whether it was just an abused example I'm not sure, but it was just a turd wrapped in glitter, cheap feeling, squeaky, nasty car. Its a real shame, as I want to like them more, but I guess in the desire to be ever more profitable and cars needing more and more equipment as standard, something has to give.