AVG free with firewall

Hello Duy,
It is advised not to keep more than one anti virus program on your computer because it keep conflict the other anti virus from installation and protection.
Hence, we recommend you to use only one Antivirus program for better protection.
Thank you

I want to use AVGf ree with another firewall software and I have 2 software: Zonealarm free firewall and Comodo free firewall.
Does AVG free  conflict with Zonealarm firewall or Comodo firewall?
And what firewall do you recommend: Zonealarm firewall or Comodo firewall?

Other user Duy Tran posting (https://support.avg.com/answers?id=906b0000000DueoAAC).
Duy, In future, to keep everything together, please try to keep the whole conversation in one question/thread to speed up any resolution. 
AVG Guru