VW Golf - 1.9 TDI / 2.0 TDI of GTI ?

[andys]

I'm sure i've read some VW info on oOple before, so maybe there's some experts out there.

My car search has led me to the car i've always wanted - a Golf.

Considering an 07 / 08 Mk 5 GTI, or one of the diesels.

Thing is there's a 1.9 or a 2.0 diesel - which is best ?
Is the 170 GT Diesel better than the GTI in the real world ?
Is the GTI worth a punt, i'd be looking at getting one with around 50K on the clock.
What milage should each engine do ?

Cheers Guys.
Andy