I bought a 1.4 TDCI at the end of april, nice car. About reliability i can't say anything about that yet.
The engine is a PSA engine, meaning it is made in conjuction with Peugeot/Citroen. It's indeed the same as in a 307, 206 or C2.
The felt thing you see in front of the engine is the heatshield of the turbo, the later versions, at least the Fiesta i know for sure, has a aluminium version or aluminium skin, that i dont know.
What i read on the internet is that if the engine fails (or the turbo) it is because it will plug up with soot. So the first thing i did was remove the DPF. Made a huge improvement in engine responsivness. Also partially blocked the EGR valve (it's electric so as far as i found it will generate a fault when you plug it completely. Still have to test that. Also that made a improvement in engine response, especially in the low rev department.
Cat is still in place (located just underneath the felt piece) but that will go also so the engine can breath freely.
As said, if you drive it on the motorway and the engine gets hot as it should be the soot won't kill you. If you drive like a old man the soot can kill the turbo and the engine due to that.
But if you remove the DPF and partially block (or tune it away in the software) the EGR valve it will lenghten the engine life.
Also oil change at the prescribed intervals (or before) will keep your turbo alive. (But that will be the same with you're TDDI i think)
That the top of the strutts are filled with grease is a good thing, mine were full of water and are terribly rusty. This is because if it rains or you wash the car water falls in the top of the strutts but it can't get out. Hence the rust or as in you're example, the grease to prevent the rust. (Good tip by the way, think i'm gonna fill mine with grease to! First Fertran, then grease)
As for fuel economy, i drive like an old man and i get around 56 mpg (almost no motorways but most 50 and 62 mile an hour (or 80 en 100 km/hr) Tires at 40 psi (2,8 bar)