AV's and Security Software Compatability

Thought it would be helpful to alot of us to list here your experiences with compatability issues between your AV and other security software you've tried to add to your security arsenal.Could save us some major headaches!I've used F-secure for over 2 years so i will start with that AV.The following programs caused a complete system lockup on my computer after install and would not recommend installing with F-secure.

Prevx1
Cyberhawk
HackerSmacker Firewall

F-secure has run well with the programs below.

Online Armor
Kerio 4
Ewido(on demand only)
All spyware scanners(on demand only)

Hope this helps.