C2K: My dad has done 7k miles in his now (GTD DSG) and regularly does Southampton to Newcastle. He gets about 48mpg on that trip, setting the ADC to maintain 80mph on motorway stretches. No way I'll ever see 60mpg on mine, found it hard to do less than 50mpg in my Scirocco, only racked 50mpg once in the GTD (2500 miles on it now).
Mine seems to regen noticeably every 200 miles for about 50 miles, was never aware of regenning in the Scirocco, always happening very subtly. The GTD seems to run a consistent 5C lower in all situations eg low load 90C, high load 94C, Regen temp up to 101C. GTD seems to take almost twice as long for oil to get to temp - I'm sure it's killing my shorter journey mpg.