I tested the drive on my MacBook Air, where they uncomplainingly on the power to the USB ports running (no Y cable required). The measured performance is on average 30-40 MB / s, the writes an average of around 5 MB / s slower than the read accesses. As usual, the power via FireWire will be significantly higher once again, not least because this interface even more power can be delivered to the hard drive, otherwise no other type of power supply offers / needs.
What strikes you immediately is the slightly larger height of 15mm, which is around 50% more than the traditional 2.5-inch hard drives with just 10mm. But that match the FW800 ports without problems in the rear wall of the housing, and the portability does this not detract.
For those who really need to accommodate a lot of data in the smallest possible space, the perfect plate - there is (currently) no alternative. That, the whole thing still goes without extra power supply, the quality of the panel further underscores only.
Strong buy recommendation (I will not soon be restored, because I now the ideal "Springer-plate" was that sufficient supplies plenty of space to me in any situation, be it a security system, a RAID-upscaling, ...)