Content Filtering Statistics. What to expect?

From: Brian E (brian_anon@hotmail.com)
Date: 12/31/02 

From: brian_anon@hotmail.com (Brian E)
Date: 30 Dec 2002 17:24:32 -0800

We currently use SurfControl to filter inbound and outbound email. I
do not expect 100% accuracy with this technology. False positives
(incorrectly blocking legitimate email) and false negatives (not
blocking Spam or inappropriate email) will always be an issue.

What is a reasonable expectation for false positive and false negative
rates (in percentages of total mail processed)?

Does anyone know if SurfControl publishes or makes claim to accuracy
rates (I assume it would be based on false positive and false
negative)?

Does anyone know of third party reports comparing these rates amongst
vendors or even in general what an organization can expect?

Ultimately, I want to quantify the performance of the content
filtering and be able to dismiss unrealistic expectations.

Regards,
Brian