Greetings!
Comodo Firewall Pro and Comodo Memory Firewall does two different things. Comodo Firewall Pro offers outbound protection (version 3 also offers system protection), while Comodo Memory Firewall protects you from
buffer overflows. Buffer overflows are commonly used for drive-by downloads (stealth download of malware).
So Comodo Memory Firewall will
not replace Comodo Firewall Pro, and reverse.
Cheers,
Ragwing