I found this article from Vishnu Tuning pretty interesting. It is basically their update on what they found with tuning the N55 motor.
Notice where it says
"A 340whp n55 with 7DCT feels about as fast as a 380whp n55 with 6AT/MT. The engine is always in the right gear and doesn't lose an ounce of steam between gears. Truly exceptional. Shifting manually results in zero throttle closure and aboslutely no loss of boost between gears. The only time you see a boost drop/throttle closure is when you let the transmissions shift itself at 7000rpm (see log below)
"
http://f10.5post.com/forums/showthread.php?t=429987
It would be interesting if we could get some actual numbers on this.
I was actually just reading the title and it didnt really convey what I was saying. I guess what I am trying to say is the performance gap between a manual and a DCT gets larger with tuning.