The 6th gear ratio on the 2.0TFSi is 26.66mph per 1000rpm iirc
Call that 26mph per 1000rpm. If you were to hit the rev limiter in 6th (which some of us can given enough road) then that would equate to 169mph (26 x 6500rpm rev limit)
26.66 x 6500rpm equates to 173.29mph (which is what i pointed to earlier)
DSG cars can Rev to 8200rpm if they have the DSG map so this theoretically would equate to 218.6mph - however you are going to need some serious grunt to get that