the etap has worked out great - except i had a bad battery, which sram warrantied - that tripp@halters took care of with a phone call.
elemnt and garmin have battery alerts on them. had one pop up yesterday.
with the etap system, it is necessary to remember to take the batteries off while transporting the bike on a longer journey, as they use
vibration sensors to be active.
i occasionally hit the wrong shifter with the etap paddle style shifting - but not often.
i also found this shift chart on the elemnt. supposed to do the same thing with the di2
I still haven't received the setup for the tallboy.
it will provide wireless cable pull to a stock derailleur.
www.xshifter.com
if it works out, i'd consider cabling my dropper for it. they are also using it for wireless activation of the suspension lock-outs.