I currently ride this combination in a 105 groupset and it suits me well as I live in a pretty hilly area just on the border between Lancashire, Cumbria and North Yorkshire. I've been looking at Ultegra Di2 equiped bikes and can't seem to find any with this combination? Any with a 50/34 crank have an 11-28 cassette. Is this combination possible with Di2? Many thanks for taking the time to read and respond.