I have been running an 11-28 Shimano 10 speed rear cassette and wanted to go to an 11-32 for some of the routes we do with more hills. I run di2 with a short cage set up the rear derailleur works fine with the 11-28 but everyone you speak to says you can't run the 11-32 so I thought I would get one and see for myself. The new rear cassette is a sram PG 1070 11-32 10 speed it's the only one you can get that comes in the 11-32, it fits fine with no issues at all and runs on the Ultegra di2 fine as well. I don't see what the fuss is about I can honestly say it works and I haven't adjusted any of the screws including the B screw. I will now test this out on the weekend and see how well the 11-32 is on the hills. The sram PG1070 11-32 was $102 from amazon.
