85kg rider - so I should be considering the 35 then. I wont be riding on mud, but on some occasions light gravel, typical on a gravel section in a road-race.

Performance matter more than comfort, but why not both. I am probably scared from years on racing with 22' tubulars on 8 bar.

35 would mean going for a wider rim (gravel?). Alot to consider

+/- 41 measured tire is really wide, but that looked like a tight fit as well. Coming from a rimbrake with 25c tires I wonder if there is any benefit performance-wise with 35c over a 32c or 30c tire. The latter should be much easier to comply with the 105-rule, and a 32 would in many cases stretch to a 34-35 width.

My frameset in size XL arrived yesterday. Order placed 30.06, sent 10.07 and arrived 4 days later - speedy process

Frame with RD and metal for FD was 835g.
Fork uncut 315g and seatpost incl. metal 150g.

My plan is to build it up with Ultegra Di2, but change cassette and crankset for something lighter. CRW HB1 cockpit 36x140 is on the way, with FSA ACR no55 as suggested from this thread.

What are you guys opinion/experience on wheelset and tire choice for this frame? Modern rims like XMCS/Zen etc. is often 25-26 IW and 34 at its widest, which should result in a 30c tire as the most optimal solution for performance.