I don't have any experience with the ATAX, not even seen one live, so I can't comment on how well it does what it says it does.

But I do have a concern with the whole idea of the "one tool does everything" idea. It could lead you into a false sense of security and cause you to rely only on having that tool. What happens if you lose it/break it? You just lost all or most of your tools.

IMO, a group of individual tools is safer; lose/break one, and you still have the others.