Need your help to understand something about Firmware/Software

Hi,

I'm doing academic work for my study, and I need someone to help me to
understand
what the benefits of Embedded NGX 8.0, compare to Juniper ScreenOS 6.2
, FortiOS 3.0 MR7 and Cisco ASA software 8.0 ?

I tried to search the web to find a comparison without success.
I've been told that the Embedded NGX gives you more feature
without the need to subscribe to extended service.
Is it true?

Thanks for your help,
Tom
.