The biggest pro I see so far (only been a few months) is that fsck takes virtually no time at all.
Another thing I've noticed (and this seems odd to me) is that my custom partitioning schema usually involves a separate partition for /,/home,etc. but "df -h" typically shows both / and /home as sharing the same device/partition. Not sure yet what that is all about.
Thanks for the speedy response and for the ping to all the experts here on Free Republic.
I'm just now getting acquainted with btrfs and, so far, am confining my still-early learning to a VM. As far as fsck is concerned, it appears that best practice is to set the pass to 0 in /etc/fstab. From what I gather (and there's a lot of information on the 'net, some contradictory) is that btrfs doesn't need a filesystem check. That's similar to zfs in that the only manual maintenance required is the occasional scrub operation.
I hope I'm not making the mistake of transferring my fairly good knowledge of zfs into the new realm of btrfs. They are different but for a n00b like me, similar enough to be a tad confusing. :)
I run btrfs on both a physical laptop and a VM.