If I had to buy again, it would definitely be a 5 door GTD+DSG, properly specced.
I would be spending less time and money in gas stations. 
There you go, that backs up exactly what I said a moment ago. Its all down to money, f**k all to do with the GTD being more desirable. 
Its more desirable at the moment because the combination of it a) looking like a gti b) "miles" better economy
Of course if fuel/money was not an issues we would all have a gti/r
There is very few people who that have bought a gti on here would hold there hands up and say ok a gtd is a better combination for me than the gti I bought. If you can then then fair play
When petrol costs were cheaper then there was an arguement for the gti, however I would expect a huge amount of people who have gti's have never even driven a gtd so cant even comment really.
Honestly I think I've fell into a hole and came out in coo-coo land.
The GTI is history, its what brought hot hatches into the world, its the badge, its the looks through the years, the famous interior, its the car itself, its the ownership, the DESIRABILITY of wanting to own one, the GTI is iconic, famous and hugely sought after.
No-one actually gives a toss about GTD's apart from GTD owners. It doesnt matter how the car runs, wither you can save 2p on fuel or wither you get 10 gazillion extra miles, or wither you can remap it to make it faster, its got absolutely no desirability at all, its a 2nd choice to someone that cant afford a GTI.
Seriously someone help me the f**k out here.