You can read more about TweakTown's Storage Product Testing Workstation and the procedures followed to test products in this article.
For the most part USB 3.0 will read and write data just as fast as SATA II. There is one feature that USB 3.0 lacks and that is Native Command Queuing. When reading or writing large files you will not notice the missing feature, but when dealing with several smaller files NCQ would be a welcome feature.
The next thing to keep in mind while we are testing is the way USB 3.0 is currently implemented in many of the motherboards on the market. The marketing claims of 480MB/s isn't the reality at this time, but next year we should see motherboards that can meet these claims.
ATTO Baseline Performance
Version and / or Patch Used: 2.34
ATTO is used by many disk manufacturers to determine the read and write speeds that will be presented to customers.
In ATTO we see the performance across several different file sizes. The N005 is able to achieve a maximum read speed of 85MB/s and a maximum write speed of 50MB/s.