Four 2.5-inch disks connected via Thunderbolt, it's definitely an interesting prospect. This way you have an extremely fast combination of disks with lots of storage capacity in a fairly compact package. If we have any complaints about the J4 it's that it's currently only available with hard disks. And while the performance of these 500 GB, 5400 rpm, 2.5-inch hard disks is quite good, we can imagine that many people prefer choosing their own. For example, four 1 TB disks or four SSDs. Or what about a couple SSDs combined with two conventional hard disks, that way you have the best of both worlds.