good idea but
One thing- Remember the Liability issue-
It is better to post a list of who had a complaint, who the complaint was against, how many complaints, etc- but dont go into the area "of this guys a scammer"
Sponsors worry about legal issues; this is why Ebay is so hands off on feedback.
If a list was out there of who has been posted against, then a reader could do a search and form their own opinions.
In other words not good, not bad, just is and its up to you to decide.
Scorp