Thanks. When you say that, is this because at around 6k miles a year it is cheaper to actually run a Gti? Or are you saying that a Gti would only cost marginally more to run and you would be willing to pay that little more for the added fun of a Gti?
The GTI will always cost more to fuel than the GTD, but the residual differences that used to really sway the balance are now gone. On only 6k miles a year, that GTI will cost £25 a month more than a GTD, but on only 6k miles pa you might suffer DPF issues if it doesn't get a few long runs over a fortnight, which will really clobber your mpg. As a GTD owner myself I would say get the GTI.
The winter mpg dips a lot more on a GTD than a GTI too.