I stopped using email filtering once I started using Avira back in the days and that was before even before I started using CFP 3.0 alpha or CIS. It never has gotten me into troubles.
From the man himself:
If you feel CIS is not protecting you enough when you browse simply run the browser in the sandbox.
Comodo has buffer overflow protection integrated in CIS which protects against:
Detection of Buffer Overflows which occur in the STACK memory
Detection of Buffer Overflows which occur in the HEAP memory