I've been riding my Ultegra 6870 Di2 about 10 times. The programed speed of rear shifting during multi-shift was too slow so I had it reprogrammed up to the next speed, one step below fastest. It still seems too slow. I'm trying to decide if I should try the fastest speed, maybe with the 3 gears per push. I have to take it in each time, a bit of a hassle.
What setting do others like the most for the rear shifting!