OMG !!!! What a difference. I was told to not go balls out for the first few hundred miles until they scrubbed in, but straight from the off, the first thing I noticed is how quiet they are. Pulled out onto a main road (just down the road from the tyre place), and had to pull out sharpish, with zero miles on them and ambient at only 3°C, and it just took off - not a hint of wheel spin at all - and that's with 0 miles !
Just got to work (approx. 10 miles), and I can already tell how much better a tyre they are. Firstly (as mentioned) they are very quiet, not just on smooth surfaces, but on rough and semi-rough surfaces, where the Bridgestone's would roar. Secondly, the ride just seems that little bit more compliant and not as harsh over the bumps (although that could be my imagination).
Lastly, I clocked my MPG after pulling up at work (to be fair only a 10 mile journey, but a mix of urban, town centre and dual carriageways), and for reference the best I have EVER had out of the GTD, which was last summer time when it was much warmer, was 64.5 mpg (which I was delighted at). Well today after arriving at work I saw this (and don't forget - mines a DSG, a manual would be 5mpg or so better).

Now it could just be coincidence, (as to be honest, I can't see a different tyre making such a huge difference to MPG), but based upon the above, I do think they will be more economical. Tonight's journey home will be the test, where I've been struggling to get over 50mpg now the weather's turned cold, be interesting to see what the Goodyear's get under similar circumstances.
So far, a very happy bunny, and they treated my alloys with kid gloves and not a mark on them, and as a bonus filled them with Nitrogen at no extra cost and used black wheel weights as well !