Performance - Intel NASPT
For an application level look at performance, I turned to Intel's NAS Performance Toolkit, which is now the main tool I use for NAS testing. It's perfectly applicable to attached drive testing, too, and I ran the File Copy and Directory Copy to / from and HD Playback and Record tests. See this page if you want more info on what the tests do.
Figure 7 shows the NASPT results, which basically confirm what we saw using HD Tune Pro, i.e. that the 3.5" drive based WD MyBook 3.0 is faster than the 2.5" drive based eGo.
Figure 7: Iomega eGo USB 3.0 Intel NASPT
The actual throughput numbers are different, of course, because the test methods are different. The NASPT File Copy results are closer to HD Tune Pro's Benchmark average numbers because both use sequential transfers.
The NASPT Directory Copy tests use multiple folders and a mix of file sizes, so show lower speed due to much more drive head seeking.
Figure 8: WD MyBook 3.0 Intel NASPT
As noted earlier, it makes sense for other manufacturers to follow Iomega's lead and move all their USB drives from USB 2.0 to USB 3.0. Any manufacturing cost increase should be more than offset by the inventory reduction cost savings.
But the supply of USB 3.0 drives is still relatively small. The only comparables I could find in 1 TB 2.5" USB 3.0 drives were WD's My Passport Essential SE 1TB Black Portable Hard Drive (WDBACX0010BBK-NESN) and Toshiba's Canvio 1 TB 3.0 Plus Portable External Hard Drive (E05A100PBU3XS).
Lowest pricing for the WD and Iomegas was around $130, while the Toshiba showed a lowest pre-order price closer to $140. Note that if you're willing to go for the older, 500 GB "Charcoal" eGo, Amazon was showing it for around $85. You'll also pay around this if you opt for the newer 500 GB eGos.
A quick check of USB 2.0 eGo pricing showed most around the same $80 price point for 500 GB. But if you can find a 1 TB USB 2.0 eGo, you might pay around $145 unless you're willing to buy from one of the lesser-known online shops.
At any rate, if you're looking for a USB 3.0 drive in a small, rugged package, Iomega's eGo USB 3.0 is worth a look.