1) It is easy to use2) The UI/UX of the application is intuitive and very simple3) The customer support team is great4) Support for Microsoft Teams5) Integration with other applications such as Slack6) The price7) There are no downsides that I know of.
The only thing I dislike about this product is that it does not have an option to add integrations like Zapier or IFTTT. We use this widget from Collaboration Widget to integrate our Teamwork integration software to our web applications. This widget has helped a lot by making it easier for our customers to collaborate in real time through our collaboration tools.