Hadn’t really gotten that far, however, I’ve found that most popular addons have functionality that already exists within Discourse itself. The appeal of addons is that generally the documentation is a little bit better and the available resources if you get stuck are pretty well fleshed out. For instance there is a wealth of documentation and issues that are “solved” with ember-concurrency so if you’re a new dev, having access to that addon would usually mean you can get up and running a little easier.
But as I said it was more of a wonder than a want.