The HURD is just a big pile of fail. Even more than most other GNU projects.
Minix 3 actually looks quite nice. Unlike earlier Minix versions, it's not just a research system anymore but aimed to be a "real" desktop/server OS.
I'd like to explore it someday, but these days my computer playtime is pretty limited ...
Here's a video of Andrew Tanenbaum explaining Minix 3:
https://www.youtube.com/watch?v=bx3KuE7UjGA