Before I deploy a new firewall I was wanting to get advice about the software. Right now it has 8.2 and I'd like to update beyond this version. It looks like Cisco recommends version Release 8.4.7.ED as being stable. I don't know what features of version 9 I would want but can anyone confirm that using Release 8.4.7.ED will be stable on a ASA 5520? Thanks a lot!