@frank I've used Things for years, and always found it an app that was smooth, well designed and deserving of my money. I first encountered it in 2008, at a This Happened event in Utrecht organised by Kars Alfrink. Used it until 2020 when I switched to Obsidian for tasks. Main issues: dependencies between tasks, grouping tasks while it not being a project, checklists to import for a task. And integration (Nextcloud calendar). From your link it seems that a lot of those have been addressed in the latest edition. Except for marking tasks in meeting notes and have them added to my task lists.
@ton I tried the Obsidian Things3 Sync plugin. It's not fully automatic, but it has a nice two-way sync between the apps.