Electronic & Hydraulic Shifting (Di2, Ui2, customisations)

Interesting idea! I read that it doesn't matter where shit is plugged in. Di2 is all modular and just requires the right number if ports in the right places.
Also dura ace levers are apparently more flexible than 6870 in this department ane you can plug whatever you want into the lever ports

I noticed that those vibe bars have a hole in the middle rear in order to thread the di2 wire through to the stem.

FYI managed to wire up an 3T aeronova bar with the EW-RS910 bar end junction box and EW-JC130 Y cable. Took me hours of fiddling but well please with the results

My understanding is that as it's plug and play you can plug anything in anywhere and it'll work, although I haven't tested that to any major extent.

Where does one buy these updated pro vibe stems from?

Looks like an insemination kit.