FreeBSD
FreeBSD is honestly one of the worst experiences I have *ever* had with an operating system. It only kinda works, I don't know how to do much compared to Arch Linux, and I can't use half the software I want to because it doesn't actually support FreeBSD.
BUT I LOVE IT SO MUCH. Seriously, despite being one of the worst experiences I've had with an OS, it feels SO much better than GNU/Linux ever did. I don't know why, but I love this operating system.
FreeBSD, Bitching about GNU
I think part of it is the fact that it doesn't bother with GNU software, which, given my sudden shift towards hating the GNU Project, probably explains a lot of it.
Of course, half my bitching about software not working on FreeBSD is that the GNU Project has its tentacles SO ENTRENCHED into UNIX{,-like} software that everything expects their stuff to be there. Thanks, GNU Project. I hate it.