I'm driving a 2016 slushie with 20,000 miles on the odometer. Only issue I've had on the car was condensation building up in the passenger side headlight which was fixed under warranty. As for the drive train, absolutely rock solid.
The Aisin transmission has delivered mothing but crisp reliable shifts. The actual speed of the shift depends on how deep you are into the gas pedal, with more spirited driving granting near instantaneous responses from the tiptronic system. Keep in mind i drive in manual mode virtually all of the time. For whatever it's worth, during the test drive of a dsg gti, i failed to notice that much of a difference when shifting.
Mod list so far is the APR downpipe with corresponding stage 2 tune, VWR 500 intake, and the complete stage 2 mounting kit from BFI. Those really livened the car up, and I've been tuned for 10,000 miles now without a single issue. Of all of those, the mounts do incur additional NVH within the cabin, but I've found that by shifting into neutral while stopped and making certain the tach never dips below 1500 revs insures a smooth comfortable ride.
To note I just finished installing a is20 into the car, but I'm probably not going to tune it at least into tomorrow. I'll be certain to provide feedback for the APR tune when I've had some experience with it.
I did consider the five speed when picking my car, but ultimately I decided that life in the bay area (with all it's wonderful traffic and hills) coupled with the fact that I really wanted six gears to play with was enough to sway me over to the automatic.
Also doesn't hurt that these auto transmissions can take basically all the power we want to throw at them, whereas with the manual anything past the stock tune requires a beefier clutch.