I used it once perhaps 10 years ago. Found it didn’t do anything more useful than what I could already accomplish with built in tools at the time. They definitely stretched the marketing to make it sound powerful and like it could do something useful.
After trying to get it to do something, and finding that it was useless for me, I haven’t touched it since.
I haven’t researched it recently. But I would expect anything it can do for APFS to be temporary. APFS isn’t even a final product yet. It’s very much in its infancy. So I’d expect any 3rd party tools will need regular updates.
And as for saying they can fix a corrupt file system, that is not a guarantee that it could fix any corruption. Some corruption situations just aren’t recoverable on any file system. It happens. And my experience is that sometimes 3rd party tools only scramble the situation worse.