The form itself is great and does exactly what it should. But the user guide is the best that I have encountered. It actually covers nearly everything in a nice, searchable PDF. It is better than digging through forums to find an answer to a questiosn that someone else asked that is not quite right. And when the answer is not there, the support has been right on it.
Yesterday I emailed support for an issue I was having and this morning, rather than just giving instructions on how to do what I needed, there was a full update to the package that had added features to accomplish exactly what I needed. I am not sure if that was done for me or if I just got incredibly lucky with the timing of my request and the timing of an update, but it was great.
The only negative that I have is withthe image CAPTCHA. I love the feature and it is what I always use, but it does dramatically increase page load time on the pages where it is being used.
Overall excellent product.