AntiSpam : McAfee Webshield 3200 or Symantec Mail Security 8200?

Hi,

One of my client (1500 mail box - 7000 incoming mails a day) told me to do a market study concerning an Antispam appliance solution (hardware-software black box). After this study, two solutions seems to be adapted for his company :

McAfee Webshield 3200

and

Symantec Mail Security 8200

We are interested only in spam detection not antivirus.

Do some of you have feedback on these antispam solutions ?

Thanks in advance