The Aeria Ultimate stem is intended to lower the stack of the bar centre so the matched bar can hit the same total stack as an undermount bar, but in overmount. So it's equivalent to a -22deg angle on the 100mm and a -24deg on the 70mm. Which may mean it's not going to be an ideal option from a fit perspective.
It's not designed for mechanical gear cables to run through the stem - they go straight from extensions to frame. Di2 cables route into the side of the stem and out over the steerer. As does the rear brake cable if you have a bar with a hole in the back of the clamp.
There is a cable stop for direct brakes - it's a threaded piece that goes into the cable exit on the base of the stem.
It weighs quite a lot, which is for a good reason that will become clear later.
You were involved in the design of it, correct ?
If so, congratulations. It's beautiful. I started taking apart a bike to rebuild using this and to use for aero and product testing.
I love it and passed my comments on to Tim.