The thought of having a bunch of separate wireless components makes me nervous, but then so did the Shimano electronic shifting until it matured into eTube. Wireless = more batteries, more communication links w/possible interference. On the plus side, install on virtually any bike without frame modification required of any sort.
BTW, we have been running Di2 TT extension shifters on our Zefiro drop bars, plus a 5-port front junction box (up from 3) for a little over a month now. Taking the extensions off is as simple as disconnecting the 2 wires from the junction box and unscrewing the extension mounts from the bars which leaves a clean set of drop bars. Done in maybe a minute if you're quick.
I know this isn't a pure TT bar setup and swapping the base bars for a TT wing bar would mean messing with brake cables, it's just an example of what we have for general use. The TT extensions stay on for cruising rollers and such, then come off when we head to more serious hills. With the extensions on, there are no arm pads getting in the way of the base bar tops, or flip-ups to get in your face when tucking downhill. I chose the "ski" type extensions as these align best with my forearm position on the flat tops on the Zefiro base bar.
The built in forearm pads on these bars are not super cushy, which is why you see some people mounting 3T pads & bars on the top of the Zefiro.
Here's some pics:
