Well, I have heared from discourse when I joined openWRT forum to seek for info about configuring my openWRT router.
About 8 months ago.
I got impressed with the forum, although at first it took a while to get used to it (it is strange when you are used to vBulletin).
It happened that I am one of the admins of one of the most important forums about photography in spanish language (ojodigital.com).
It was in Vbulletin 4 and it was decaying as most of the forums, due to social nets and the software being old and not well adapted to tablets and mobile.
Meanwhile or forum transition fro a private owned forum (owned by the founder) to a comunity based forum. We created a photography asociation to sustain the forum and other activities.
We wer seeking for a goot forum software and I had no doubt discourse was the best I knew.
So we migrated to discourse.
We have not migrated old content, as it is a lot of information (about 15 years) , with hundreds of thousands of users, much of that info is old and most users do not participate today.
So we begun from scratch in order to get a much more light forum. And we do not have the expertize to do the migration (neither in vbulletin internals, nor discourse).
We are very happy with the results (https://foro.ojodigital.com).
The old forum is now closed but still functional.
I am trying to get a static pages version (plain html) in order to archive the old forum (using wget)
But I am having troubles getting it to work, as urls to CSS and other resources do not work even if I try to generate relative URLs.
It would be great to get it archived and close the server dedicated to vbulletin.
If I can not do it, we will close it in a few months and all that info an photograps will be lost.