My verdict: the art of task management, but a closed ecosystem.
Things 3 isn't just a todo app, it's a functional work of art. The design encourages daily use. But Apple lock-in is real: no Web version, no Windows, no collaboration. The one-time purchase (80 euros for everything) is economical in the long term, but the lack of product evolution worries some users.
What I like less: Apple-only with no escape, no team collaboration, almost no integration with other tools, no web version, high entry price with no way to test.
My advice: if you're 100% Apple and work solo, Things 3 is a one-time investment that will serve you for years. For collaboration or multi-platform, take Todoist.