I really like the DSG so would definitely recommend. Had it in my last 3 Golfs - Mk5 GTI, Mk6 2.0 TDI 140 and now Mk7 GTD
When I first got it was mainly for the power but these days I appreciate its relaxed nature and it works very nicely in combination with the Adaptive Cruise.
The GTI in question here being a June 2015 will definitely have DAB, but you're on the fringe for whether it will have the 2016 changes (KESSY, Winter Pack and Nav)