To be honest guys, I don't think we will really know what the ACC is like until one of us actually gets to drive it. Don't forget that the ACC is all new on the MK7 platform (ACC MK2) and now has the ability to regulate the dampers individually (rather than across a single axle like the previous incarnation), so my guess is that it won't compare to the MK6 or Scirocco systems, but instead will feel totally different.
Judging by the reviews on the GTI, all seem to heavily praise the GTI's ride (and all seem to be fitted with ACC). Not one journalist I could see, and commented it's too hard or too soft, most have said, it's perfect !