They work great, just be careful how much power is required for the drive you plug in. If you have a drive that draws 850mA or more, the Mac's USB port won't be able to power it since it only puts out 1A. It's not the case's fault. If you're using FireWire you'll have more power to make it work, or if you get a Y/twin tail adapter and use two USB ports it will work. If you're using a less power-hungry drive, it'll work just fine. Again, this is how electricity works, and Mac limitations have nothing to do with this product. I have purchased over 50 of these devices for a consulting firm and they all work exactly as expected.
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