I've got a 56 Mondeo 2.0 TDCI.
Its my first car since passing my test earlier this year.
It came with one owner (company car) with a full Ford service history. It runs great and it's economical returning around 50mpg.
I had a knocking and stuttering on start up so decided to replace the DMF. Upon opening the gearbox I found it had already had a new DMF and flywheel. It turned out the issue I had was with a temperature sensor. A quick software update from Ford and it was all sorted.
The radiator fan wasn't working so the aircon got red hot when stopped. This is a common problem. The electronic box dies and is very expensive from Ford. I fitted a prefacelift fan and control box and spliced in the wiring and it work perfectly and only cost me £10 for the fan, surround, rad and air con cooler.
I'm still a little paranoid about injectors but if it happenes it happens. If you search the internet you will find bad reviews on everycar.
Take your time looking for the right car. I opted for a Zetec Nav spec as I couldn't find a Ghia spec at the time. I've since added electric rear windows (£30) full heated leather interior (£35) auto dim rear view mirror (£15)
Parts for Mondeos are so cheap and so are the cars themselves. I was recently looking for a Focus for my Daughter a couple of months ago and I couldn't believe how much money they were going for for the spec/age. They make the Mondeo seem a bargain.
Buy it, look after it, love it and if anything goes wrong just accept sh*t happens.