This is a pretty solid spam solution. We used to outsource our filtering but determined that we needed to flexibility in options than what the hosting provider could do.
There really isn't much to say in regards to cons for this product. It was pretty straight forward in setting it up. I had to call support once and they answered the phone and my question very quickly.
We are happy with Barracuda and will look at their other solutions. (Posted on 6/14/09)