I’ve used it over USB 3 for several years. The thing is that USB controller hardware isn’t perfect, and the bus can break down. If it does break down, chances a

I’ve used it over USB 3 for several years. The thing is that USB controller hardware isn’t perfect, and the bus can break down. If it does break down, chances are the pool metadata becomes corrupt, which means the pool is irretrievably lost. In theory, a corrupted zpool isn’t a problem, because you should be backing up your pool all the time. In practice, it’s a double-edged sword. The downside is that whenever the pool becomes corrupt, you have to do a restore. The upside is that whenever the pool becomes corrupt, you get to do a restore, which you probably wouldn’t do regularly otherwise. Whether or not your bus is going to break down sporadically is unpredictable. With one Mac, it never happened. With another, it’s happened twice a year.