I bought some various adbrite ads for a hobby site without carefully reading the fine print about the ads being recurring by default. Being a hobby site, I didn't pay a lot of attention to the campaigns, until my credit card was declined at a restaraunt. Fortunately, it's my online-use card with a low limit, so it wasn't a financial hardship, but I could see a potential for financial disaster! The $200 I voluntarily spent became $500 by the time I noticed.
Other than this quirk, I found Adbrite easy to use, and fairly effective at bringing in lots of new registered users to my hobby forum. Thing is, virtually none become returning, posting members. This could be due to the nature of the content in my site's case! Still, I'm wondering what luck people have had with adbrite on their ecommerce sites? Good CPC and conversions, or no? Thanks.