here are 2 comment from the newsgroup where I found it,

"Works great. I bet I was bombarded with 200 sobig infected e-mails
yesterday. Since this program keeps stats, it will be interesting to see how
many it catches."

"Thanks for this link, Bob. I've been using this program all day today and
it intercepted 1348 bogus emails saving me a lot of time. Unfortunately it
doesn't intercept "undeliverable" messages so there were a few hundred more
that I had to ditch manually."