Not sure on a comparison but my Ultegra Di2 (R8070?) are much shorter than the regular non disk shifters. I find them less comfortable that the regular ones on my other bike.
Interesting. I have some trp hylex levers and I am looking for something shorter. How long are the r8070 from mid bar to the levers start to turn up. Like this drawing with trp hylex (59mm):
How long is the reach on shimano r785 levers vs r9170.
On this image it seems like they are the same, but on other places on the net people write the r785 is 5-10mm longer to the upturned hood.
https://handsonbike.blogspot.com/2018/01/shimano-road-hydraulic-disc-brake-di2.html
I guessing that ultegra r8070 has the exact same shape as dura-ace r9170