My second time doing this retrofit on a mk7, just as easy as the first time. I prefer the plastic pop rivets for install, I didn't have issues with the last ones and I don't expect to have issues here.
I do find that having had both a GTI and now my Alltrack, the wagon seems to be quieter in the rear anyway. I do remember on the GTI that it quieted down the rear, I didn't notice much difference here with my little bit of highway driving. Though the extra aerodynamics will much appreciated since the 4motion variants get worse MPG than the fwd counterparts so every bit helps.
Now to go through the other retrofits to see what else is compatible with the 4motion MQB cars.