I drove ~35 miles on my 91 oct OTS STune today, but SoCal traffic did not allow me to do much...freeways were a parking lot...
Still my experience was exactly the same as fenster reports above...I drove pretty conservatively being the 1st time, and only went WOT around the last 5 miles of my commute. If you go "granma mode" @ with my DSG, you can hardly know the difference from stock. It is very refined.
The even with half throttle though, car is definitely more lively and the engine sounds angrier and feels much more igor to spool up. I did notice downshifts in Manual while simultaneously getting off the throttle were a bit crude in the beginning, but seemed to improve as the car adapted.
There is some increase in torque steer, as the map at 22psi or so, does ask a lot more from this FWD over the stock tune.
Trims appeared to be fine with our CA 91 pump gas right out of the box. Perhaps I will get some logs over the weekend as my current 91 tank runs low.
I have to admit that although I have all the COBB OTS maps, I don't know if I care flashing back and forth to see if there is a difference...more happy to go for a very mild E85 blend and try the 93 S-Tune instead for my next tank...