Asterisk 11 or 13

I am currently downloading free pbx 64 bit 6.12.65.iso
Before i begin the insall of distro 64 bit free pbx 64 bit 6.12.65.iso install would you recomend
asterisk 11 or 13
Stable-6.12.65
currently running centos 6.3, asterisk 11.03 free pbx 3.2.11

I found
Protecting your Asterisk / FreePBX Server using a host Firewall at…http://wiki.freepbx.org/pages/viewpage.action?pageId=33882179

looks good but i noticed it required free pbx 12
does this mean i can use the ip table script now?

Digium considers 11 and 13 stable (the even numbers will always be experimental, never use them in production) , however the integration between FreePBX and Asterisk means that FreePBX is still Alpha AGAINST Asterisk 13 :wink:

Easy answer stay with Asterisk 11 and upgrade when the admix is considered fully stable.