I'm a bit of a productivity geek, and like many of us, have rotated through many planning & task management apps. One of the things that often sees me swing from one app to the next is the level of complexity. Sometimes my projects and work need a high degree of granular planning and tracking, and sometimes I need something much simpler to keep my mind clear.
Momentum is definitely on the more complex & highly structured end of things, and so if you are a person who prefers extreme minimalism or are just in a phase of your work where structure is more of a hindrance than a help, then this app might not be your speed at the moment.
On the other hand, if you are amid a complex enterprise, responsible for many deadlines, or are just a person who prefers to have clear and structured guidance for your day-to-day work, I don't think there's another app with more to recommend it than this one.
From the earliest stages, the team has centered creating something unique that supports the philosophy that Charlie Gilkey & Productive Flourishing have discussed in their work. This isn't just a cookie cutter app that provides a slightly different UI to essentially the same feature set. It keeps you away from the mindless management of one urgent or poorly planned task after another that can become common when things are intense. Its structure forces you to carefully consider how much you can do - and what the costs are of adding "just one more thing" into an already crammed day.
Anyway - while I will doubtless still use some more unstructured and flexible solutions for the work and the times of my life that warrant it (Things is my favorite), Momentum is my go-to for high level projects, intense times & any time I just crave a more structured approach to how I spend my time.