After using several form builders for Word Press, this is by far the best. Granted the demo limits you to six fields plus a submit button, but it's enough fields for any basic contact form and for checking out how well it works.
My favorite feature is how it stores all submissions in a database within the WP CP. This means you don't have to just use the email option that many other form builders restrict you to. I also love the built in recaptcha feature and how you can separate forms into pages. You can also add custom HTML onto the form. I used this to put in a user agreement and then have the user put in a recaptcha to approve it.
The only feature I saw missing was a URL field. It would be nice if the user could put in a URL into a URL specific field and then it would be a link automatically in WordPress.
Thanks for developing such a great plugin for WordPress. =D