Operation is then a simple matter of plugging the unit into its power supply, and attaching the eSATA cable to an appropriate jack (for the security conscious, Icy Dock provides a cable attachment point as well). The drive was recognized immediately by Windows, but for some reason didn’t initialize. A quick trip to the Disk Management administrative applet solved this, and I was up and running after a ‘quick format’ that was over in the blink of an eye – using a 500GB Maxtor SATA300 drive. The drive ran cool & quiet, even with passive cooling and even during benchmarking, with a pleasant grayish LED indicating power on status and drive activity.
 
And one last cool feature... check out the “switch-feet” in this picture.  The press of a small button on the unit’s I/O panel deploys two pairs of feet for standing the MB559 on its side!  While they are arguably too narrow to prevent all accidental tipovers, they do have nice rubberized surfaces, so the drive feels secure and vibration-free even on a slick surface.

HDTACH Testing
To give you a better idea of how the new Icy Dock unit performs compared to familiar storage mainstays, I used the latest build of HDTach, and benchmarked the following configurations (my benchmarking practices and machine specs are detailed HERE):

• The MB559 was fitted with the 500gb Maxtor SATA300 drive, with 16mb cache, shown above.
• ICHR7 RAID0 Array, with 2x74gb Western Digital Raptors, SATA150
• JMicron JMB36X SATA300 Controller, with Icy Dock MB559 in eSATA Mode
• Generic USB 2.0, with Icy Dock MB559 in USB Mode
• Generic IDE, 250gb Western Digital UDMA-5 drive, with 8mb cache

Testing revealed the following figures:

Drive	Sequential Read Speed	Burst Speed	Random Access Time
RAID Array	121.5	231.5	7.7
Icy Dock, eSATA	60.0	123.3	15.8
Generic IDE	50.3	92.9	11.8
Icy Dock, USB 2.0	36.4	37.5	14.5

A couple of things should stand out here. Not only did the Icy Dock enclosure, in eSATA mode, crush the same drive when used over USB (as expected), it actually outperformed what once was a pretty high end Western Digital IDE drive, one of the first with 8mb cache! That’s right... an external enclosure outperforming a speedy internal parallel drive!  It is indeed funeral time for PATA technology.

I should however point out that there is a cloud behind that silver lining... namely, where is SATA300 throughput?  I used an SATA300 drive and controller, but the results above look more like SATA150, with a burst speed peaking at about 82% of the former SATA standard.  This must be a limitation of the hardware controllers needed in an external enclosure such as this, because a quick search around the ‘Net showed very consistent results among the eSATA products currently on the market.  All in all, though, very solid performance.

Conclusion
This is an absolutely fantastic product, which I can whole-heartedly recommend to anyone interested in external storage, especially those who have suffered through those long USB or FireWire transfers. 
However, I did have two areas of concern:

The first is pricing.  My favorite online retailer lists 20 some-odd eSATA enclosures for sale, starting at about $17, but the MB559 is second-most expensive at $69.  In all fairness, none of the bottom-shelf products sport a removable tray such as this unit, and Icy Dock’s build quality is extremely high, but there is definitely a price premium at work here.
Second, where is the spare drive tray?  It is truly amazing that none of these products include a bare minimum component to accomplish the drive swapping that they all – not just Icy Dock – advertise as a highlight feature.  The tray itself is quite minimal, and one would think the cost quite small to include one with the unit.  This small step would effectively distinguish the MB559, set it apart from all others, and easily justify the slightly higher price.  I am truly mystified that none of the companies producing eSATA enclosures have seized such an easy opportunity to stand out... and if any of them are seeking a Heavenly Hardware Gold Hardware Award from me, they soon will!