Not sure what you're looking for here. I run both Shimano and SRAM cassettes and find both perform well. If you don't regularly need 34x28, then I'd put in a vote for 11-26 as my favourite hilly terrain cassette. The 21-23-26 progression is tight enough to not cause me to fark up my cadence too much, and I've gotten up some absolutely ridiculous grades with a 34x26.