Your experience with a faulty controller mirrors the issues I experienced with the faulty ASM1061 controller; unstable and flaky under load. Recovery was quite

Your experience with a faulty controller mirrors the issues I experienced with the faulty ASM1061 controller; unstable and flaky under load. Recovery was quite undramatic once the affected disks were put on a known stable controller. Btrfs-check followed by a scrub got everything back in order. And btrfs gives me one thing that ZFS can't do (yet): a completely flexible RAID1 storage pool where I can add and remove disks as I want, the only limitation being that no one disk can be larger than half the total pool size. For me, this flexibility is a killer feature.