WPHelpDesk is extremely easy to setup and use, it integrates easily with your existing site – simply creating two pages and adding shortcodes and I like the fact you can also integrate it with other form plugins like Gravity Forms, Contact Form 7 and so on. The interface uses the standard WordPress UI so your support agents will be familiar with it. The saved replies feature will be extremely useful! If you are looking for solid helpdesk solution for your site then check it out.
Oliver Dale Owner, WPLift.com