[j3097736]

I purposefully ran btrfs on a malfunctioning drive for over a year (kernel 3.12, only metadata dup), much more reliable than ext4 which would lock up the entire filesystem on read/write failure and often go read-only, with btrfs the only visible signs of malfunction were dmesg and the scrub log.

Also been using it as / since 2012 with no issues.