I like ZFS best. But it requires Solaris portability layer for linux, which isn't great, and since it's not just built into linux it's easy to get into a state where ZFS isn't working.

So I moved to btrfs. Btrfs gives me LONG delay problems, sometimes more than a minute (!) before my editor will let me type again unless I'm on an SSD. So I moved my active files to an SSD. Still, I can't believe btrfs is still such shit after this many years, compared to ZFS which was really good early on even.

I've even considered leaving linux for Open Indiana. The file system is almost that important to me.