In it's old form, Active Collab offered our team the transparency into every project that we desperately needed. It allowed various members of the team to see what was going on at different stages of the project. I loved that it came with a desktop timer that made it really easy to track time to a certain project.

I like the interface, especially of ActiveCollab 5, which is massive UI/UX improvement over AC 4. The product works and feels like Basecamp, but drastically expands the functions of Basecamp with invoicing, estimates and modules that allow you to increase your collaboration with Slack. It works well out of the box, minus some of the configuration which is really ridiculous in a lot of ways.

It's relatively easy to use and has an intuitive interface so even some of our less tech savvy or software oriented team members can use it without an intense amount of training required.