My skepticism towards carbon fibre bows was part being conservative and also an earlier experience with a bow which was mildly speaking uninteresting. Within minutes of playing with an Arcus bow my opinion was changed. Instead of using a new material to recreate a clone of an old concept they came up with something quite different. The design of this bow allows to reduce weight, which gives more freedom in the faster, lighter strokes, and its hollow stick resonates extremely well, producing a strong singing tone. The strength of the material allows for a greater length of the stick, like that of a violin bow, and gives it a great lateral stability, for me a vital factor in projection of the sound.
The makers of Arcus ask you to try the bow for a week without playing a heavier bow, to get used to the unusual weight. For me the deciding factor is the balance not weight, and that is not any different from a good wooden bow. I have no problem switching back and forth but at the end I still play with the Arcus.