Whatever works for you 😉
Imperial hardware is 100°, so it would be closer to the angle of a 120° drill point. But if you want a nicer finish, you can't beat a burr like that, especially for carbon fiber. The burrs cut a lot better.
Metric screws are 90°. Drill points are normally 120°. The bottom of the screw will run into the countersink before the head sits flat, which with carbon fiber, could cause it to delaminate. If it were me, I would invest in a 90° burr like this one...
SK-5 Cone 90 Degree Tungsten Carbide Burr...
The only things I have left that belonged to my dad is an old Unimat miniature lathe/mill and my Fender Malibu guitar.
I need to grab me a 1/10 car stand. Or maybe I could just go design and print one 🤔