[Asterisk-Users] Advantage of Cisco 7960 with 5.x firmware?

[Peter Pauly]

I'm currently running firmware version 3.2 on my
Cisco 7960. I've seen on the list that several 
people are running the 5.x latest versions. 

I've avoided going to higher firmware versions
because I'm worried about potential problems
or issues with the encryption mechanism used
in the later firmware versions. (Once you 
go to an encrypted firmware version, you can't
go back, right?)  

For those of you who have gone to the newer
firmware, what features or benefits have
you seen by going with the newer firmware?