I seriously used digiKam for the first time to select and organize the 1600+ pictures of the second edition of Scambi Festival. It was messy and itchy at first, I needed to figure out a lot of stuff and make up Scambi Festival digiKam workflow, but I ended up loving it. Above all, what makes it awesome is that it groups together a lot of features and tools I needed that I struggled with before. Everything is in one place and their use is perfectly integrated.
I would love to start using it for my personal media management, but I have 20000+ pictures so far, and it is a huge amount of work to switch to such a system, regardless of its greatness. Furthermore, I gotta learn how to effectively integrate it with Darktable.