It seems like a lot of the risk comes down to the patient's genetics and the doctor that is working on them. The cons seem to be very minimal with the right doctor. Septal cartilage seems to be the "safest" overall but it can't be used with all surgeries. Ones that require more work, it would not be enough.
In terms of synthetics, I would avoid gore-tex and PCL mesh (especially PCL, it is not considered safe at all for nose jobs!).