About a year ago I had the pleasure to play a carbon fibre violin. I did post about it somewhere back in history here.  It was not too bad. I will agree, like stated above, they are very pricey. It is not unlike any other instrument with regard to cost for quality. The weight, although a bit different, was not cumbersome, gangly feeling or obstructive to playing.

I was able to hear it with 3 different types of strings on it including Gut strings which sounded the worst of the lot. These instruments are fabricated to a specific formula/process, but I imagine there is still a variation in sound quality across a broad range of them. The manufacturing process itself, the purity of the substrate, the cleanliness and temperature during the molding/cooling, calibration and precision of the automated resign injectors, CNC cutters and heating unit quality and calibration, even the QA process throughout the manufacturing will all affect the final product. More then likely on lower end models, you will end up with epoxied cracks and filled holes, re-heated and recurred products covering blemishes and random manufacturing defects.

Would I own one if it became available at an affordable cost? Absolutely I would.