i doubt it..the eden cpu is not as powerful clock for cloack as any current or last generation cpu..the 550 will more than likely choke on asl 5 unless you are using it for home use..go for the 700 plus range for anything above 10 ips or if you are going to use the more cpu intensive stuff like ips and/or spam trapping.
Which version do you plan on running? v4 or v5? v4 should run fine. v5 would be slow to configure but should run OK once set up. The only issue is that the reason to go to v5 would be it's additional reporting, spam/virus capability, and IDS/IPS. All of which would bring this machine to its knees. It can only hold 256MB of RAM which is the minimum for v5 but is great for v4
We have a quite similar thing (LEX Light) with 566 Eden and 256 RAM. V5 runs okay, but it has only 1 rather idle server and no lan users behind. It doesn't have many features enabled, but the hw report shows: 0.4 processes, 120 MB memory used, 3MB swap for last week.
We have another in production use with V4, runs okay for 5 lan users and 5 internet servers. Almost every feature enabled. For this machine reporting tells: 11% cpu, 185 MB ram, 32 MB swap. This is the monthly avg.
So I think it is pretty much up to the needs and usage. I believe this platform will be still okay for 10-25 user office, or a smaller office with few servers. If you add a lot of vpn, proxy usage and intrusion protection, you might need more ram than 256.
