Hi,

I feel its better to check and get idea by yourself. 

As there is multiple free and paid apps, if you are not satisfied with the available free modules, you can go through the index files of paid modules and see which module satisfy your requirement most. If you didn't get enough information from index file, you can try to get the demo link from the author and go through the system and see.

If you are going with the available free modules, just check the ratings given for the modules, check the index file, and finally you can download those modules and install and see how it works.

Also you can check the download count of each modules.

Free Modules:

1. Website Help Desk / Support Ticket

2.HelpDesk

3.Bureaucrat Helpdesk Lite

Thanks