Wait...why is your index finger coming off with Shimano? It’s push push....unless you choose to release with finger. It has that option, unlike Sram...Seems like they are not part of the sram geoblock. I have zee stuff on the hardtail and get on with it ok, but overall just prefer the sram shifter ergonomics. Makes more sense to have a system where you can keep index finger on the brakes whist shifting ( and commence controversy....).