I had my Focus' transmission reprogrammed a couple of weeks ago. The transmission was ok to start with, except that it went into neutral on two occasions when it was supposed to be in S3, an annoyance and a safety hazard. Mine was built prior to August, btw.
The differences after reprogramming are minor, but effective. The launch seems a little smoother and as of yet, the trans. has not gone into neutral on its own. Shifting may be a bit smoother than previously. Gears may be held a little longer but with a light throttle, the car still shifts at very low speeds, which is good. Kickdown seems to come with a little lighter foot on the pedal, now. In all, the driving experience is very nice, especially combined with the car's handling and ride.
Ford customer service reps., including Noemi, and the dealer treated me very well. The dealer had the car overnight to address a little rattle, in addition to the reprogramming, and they rented me a car, which I appreciated.