Don't own sram Etap, but question for someone who has tried it or other wireless bike stuff.
Have you ever experience any type of radio jamming making it stop working?
Here's why I ask: every time I approach a certain fire station in my town my heart rate monitor stops working, wireless cyclometer a stop working. The station has a repeater tower on it. Once about 200m away everything comes back up. This is annoying, but being unable to shift gears in this situation would be a real hassle.