It's better than nothing.

Integration with Constant Contact was easy. The plugin’s forms integrate reliably with all of your account’s mailing lists (so far, no problems here). The form designer is pretty weak. Input fields are widget sized and you’ll need to write custom CSS to get the forms to look acceptable on anything other than a sidebar. There are options for several Custom Fields in the form designer, but no way to map them to fields in your Constant Contact mailing list. The plugin has fields for home phone and work phone which sync nicely to CC, but there is no field for mobile phones (other than a custom field, which can not be mapped). If you absolutely need to add Constant Contact form integration to your site and you aren’t picky about how it looks and don’t have really demanding needs, this plugin will do. If you need any kind of real-world usability, though, you’ll probably have to drop some cash on another premium plugin.