I'm a hobbyist who has used PS for 20 something years now. My issue with Affinity Photo is that you can use 85% of your PS knowledge and workflow, everything is the same but that last 15% is awfully, unlogically different and will drive you mad. That last 15% feels like it was made by people who do not understand why PS does things the way it does. Meanwhile my statement cannot be true, because Affinity nailed the firat 85%, but just cannot comprehend why they couldn't copy the last 15%.
The keyboard actions alone are maddening. Trying to switch tools, exit a text editing mode, change tool properties, all can be very frustrating to do with the keyboard.