I started using the Virtual Smart Agent back in the end of 2008. I used it all 2009. I kind of set it up and it go. I just remembered that I had it when someone had put a question to one of the agents and the question was not in the database. So in logging in to take care of the question, I looked at the stats. Here are my stats for using Virtual Smart Agent.
You can see where I have 5 people added to my email list, and I got 5 sales ($200 at least as its on a monthly membership site – so probably more) for spending $99ish (hint, if you go off the page they will offer you a deal).