I was on a group ride recently, and we hit an unexpected very short, steep climb at a bend in the road. All the riders climbing while seated, in a reasonable gear, had electric shifting. The rest were grinding up in a way too high gear. The instant and drama free front and rear shifts are really nice on rides with lots of small rollers, or on these sudden situations.

A couple of years ago, even one or two Di2 bikes out of 12-20 riders was somewhat unusual. Now I notice maybe two to six on a ride of that size.