The Cinq Shift:R trigger shifting system was for the most part very good, but the shift levers themselves were not to my taste.
Part of the problem was that they didn’t pull enough cable, so it was only possible to shift one gear at a time. I suspect this is because they appeared to be literally the same design as the Rohloff version, where the required cable pull is not as great. I couldn’t really do much about this, though I did perform a little thought experiment about how I might design a new linkage based shift lever that improved the situation. The other problem was that I felt the pivot point of the lever was much too close to the bars, so the ergonomics of pushing it had the effect of the lever moving away and inward from your thumb. On top of this, there was a slight chamfer on the edge of the lever that my chunky thumbs had a tendency to slip from. The solution was to 3D print some clip on extensions for the shift levers that introduced a slight concavity and texture to the levers.
This didn’t solve the underlying ergonomic issues, but it did at least mitigate the thumb slipping issue somewhat.