I made the jump from older Shimano 105/Ultegra 9-speed mix to Sram in 08 when I picked up a Specialized Tarmac setup with Sram Rival. Initially I was very happy, but did experience the occasion miss-shift, i.e. try to down shift, the chain moves to correct cog but the lever did not click into the correct ratchet position, release the lever and I end up with an up shift.
I figured this issue would go away as I get use to the levers, but 2 year later and I’m still having problems. I’m not sure if I just haven’t gotten use to the levers yet (or ever will at this point), if this is an issue with the 08 Sram Rival Shifters, a general issue with all double-tap shifters, or something else. This happens even when the setup is cleaned and dialed-in, but is a little more frequent when things are dirty or a little ‘off’.
So which is it, operator error

, the 08 Rival Shifters, all double-tap shifters, or none of the above?
What I really want to know is if the issue will get better if I swap the levers out for newer Force or Red.
If this issue cannot be fixed or is operator error, then I’m going back to Shimano or jumping to Campy.
Thanks for the feedback.