Originally Posted by
DubT
I am using Dura Ace front and rear Derailleurs, with an 11/28 10 speed and it works well, I think that i would prefer a 12/27 and will probably go that direction with the next cassette, if I can find one.
Wayne
The 12/27 is nice except for the jump from 21 to 24 that is 14.2%. I wish Shimano would have used their old 9 speed 12-25 cassette jumps and just added a 27 to it to make the 10 speed 12-27. That would have resulted in a smaller max jump of 13.3% I would rather loose the 16 tooth cog and not have the jump from 21 to 24.
As a result we use the 12-25 as much as possible and only use the 12-27 on hillier routes.