Ok Tom,
Most of my drilling of carbon fiber is on light aircraft maintenance and repair.I specialise in the repair of advanced composite sailplanes. I tend to use a slow twist solid carbide drill, to avoid chipping up and delaminating the surface layers. However I have never really paid any attention to the particular grade of carbide used.I just change them when they get dull.
I have more problems drilling aramid fiber, avoiding the fuzzies, cutters have to be sharp for that. This is most likely not going to help you much, but it may provoke a response from other users now they know what you are looking for.
B.E.