But is was wondering if the version that you can download from this thread is the final version?
Yes, it's the only version there is at the moment.
And is there (maybe) a version where you can pass a millisecond argument that will ensure that the movement will take exactly of time to complete?
One could build something like this by reading the current position and estimating the best speed. The main problem will be the speed control. At the moment the speed can be regulated just in a small set of discrete steps. Speed increments in between aren't supported. I wrote it this way because it was rather simple to tack that on the default Servo-library. The main goal was to provide a rough speed control to make movements visually pleasant for landing gears and canon turrets on model crafts. With an arrival time this simple model will start to unravel fast.
Korman