https://www.gnu.org/software/emacs/manual/html_node/emacs/Ba...
Here is a good summary:
Surely, a good investment for anyone above minimum wage who does ascii art periodically on a mac?
1) It's very cheap and a great show case for a small niche Mac app that's both beautiful and works well
2) The two times per year I use it, it's already worth it and fun to play around with.
The last blog entry I saw was that it's been put into maintenance mode. If your interest has fizzled but you still want to keep the product out there, that's a great use case for open source. I'm just not that inclined to pay for something that's not being actively developed.
Obviously at some point last year it got a new feature (yay). That speaks to the app itself being feature incomplete.