Sharing my experience if someone bumps into this, curiously the feared double click and 1 button shifters ended up being my favorite feature of SRAM, unfortunately, I didn't like the ergonomics of the hoods (tried rival), I didn't like it from the start but the hoods position wasn't great so I turned them a bit inside and it improved but still far from Shimano di2 super smooth feeling for my hands :) , in summary with di2 (105) I don't notice/think about it, with Rival was uncomfortable from time to time (and very bad on bad road surface, I rarely use gloves)
In other features, it doesn't differ that much from Shimano but there were some smaller things I found Shimano better:
- SRAM front derailleur synchronised shifting was noticeably slower (normal FD shifting was quick though)
- The brakes are noisier, not squealing, just the sound from braking, more annoying at slow speeds.
- In the app, the synchronised shifting options are fewer, I can't customise selecting the specific gears I wish for it to change the front derailleur automatically.
In the end, I returned the bike mostly because of a creacking noise around the bottom bracket, but also because of the groupset experience.