Sorry nothing to add to the OP question other than the DA hubs I have are tops although I did have a rear hub with a faulty engagement mech. The three pawls were out of synch resulting in engagement with a single pawl. The ratchet would then slip and re-engage with a hard clunk. Replaced no questions asked but a surprise defect for DA.
I too am debating between a C35 and A23 on Chris Kings with CXrays. I have an A23 on DA hubs and the ride quality with 28/32 drilling will not be surpassed. Aero? Well no, but superior in all other respects. The risk with the Shimano stuff is if you damage a rim or hub 3 or 4 years from now you may have a problem obtaining a replacement. The switch to 11 speed could compound this issue.
Some interesting points.
The thing that interests me is the 'ride quality' that people refer to with the 23mm rims. However, as a purely social recreational bike riders who has tried lots of stuff over the years, to me, sometimes it all feels the same?!?!?.
I did run Shimano C24 four years ago and still to this day cite them as the best magic carpet style ride yet, which was detectable. The thing I noted since I sold them to fund other wheels is nothing has given me the feeling of a top end wheel like these, hence looking at the C35. I have tried a few others Zipp included but nothing hs touched them. Perhaps it was my first true upgrade wheel as you only get that 'bang' once I think....