Personally, I'd never want to ride with eTap - I can't imagine needing two hands to fully operate the rear derailleur (and the front). For me, one of the main advantages of electronic shifting is the convenience of shifting and I've taken advantage of being able to add extra buttons to Di2 to allow me to shift from multiple hand positions. The eTap approach of having only one button per hand would infuriate me because it would be so much easier if there were more buttons per lever to give more shifting options.

I agree that eTap is simple to operate and learn, but that doesn't stop it from being inferior. BTW, I also dislike SRAM's mechanical shifters for the same reason, more buttons/levers would be better. SRAM products seem to be like many Apple products that sacrifice buttons for the sake of style and simplicity, but in the end lose function and control. For the mechanical levers, SRAM were forced to invent something like DoubleTap to get around all of the existing patents, so I don't know if that was also the case for the electronic group, but it certainly wasn't designed with functionality or ergonomics in mind.