I had a 2013 stage 1 ST. Intake, borla catback, Unleashed Tune. Quick for what it was, but didn't feel nearly as strong above 60mph as my Cobb Stage 1+ GTI w/ DSG. The GTI still has monster power at highway speeds, where the ST would kinda lose steam. It's also worth noting that the ST only has a K03 turbo, which is smaller than the MK7.
That all being said, my ST would hold about a car's length ahead of my brother's 06 GTO that runs high 12's up to about 75-80, then the GTO would catch up and start walking me. With the improved top end of the GTI, I think racing my bro's GTO will be a little more interesting this year. Once I get a dp and stage 2, don't think the GTO will be able to catch up.