I regularly cite it as an alternative to mainstream desktops and example of a microkernel system that performed well. Here's a post with it and a bunch of other systems with excellent properties worth copying:
We were discussing microkernels vs monolithic recently with BeOS as example. Opponent believed compilation times and apps doing many file accesses (web server) should be really slow on such a system vs Linux or Windows. Did you do either of those on BeOS and alternatives? If so, what was your experience with that?
Note: BeOS is a special case since the filesystem is a database. So it cant prove his point unless it has XFS or something. But still curious.
https://news.ycombinator.com/item?id=10957020