I know this is an old thread, but the workaround I found was to use a delayCall to kill the tween when you need it to stop spinning. For example, my prize wheel uses the Expo ease to slow to a halt over 20 seconds. The last 5 seconds are so minor that Flash isn't rendering the frames, then it just jumps to the last frame. it took some trial and error, but setting a delayCall for 15.5 seconds kills the tween just as it's slow enough to not notice.
I hope that helps someone!