It is a myth than USB 3.0 can crush eSATAp (eSATA/USB).

Stephen Foskett, Pack Rat reviews IOMEGA USB 3.0. shows that USB 3.0 can’t even match SATA 3Gbps. You can also check out an older CruchGear review here.

Here are the theoretical specifications fyi.

SATA Revision 3 = 6Gbps (750MB/s)

SATA Revision 2 = 3Gbps (325 MB/s)

USB 3.0 = 5Gbps (625 MB/s)

USB 2.0 = 480Mbps (60 MB/s)

According to the review SATA 6Gbps can reach 300MB/s, while SATA 3Gbps is 200MB/s.

USB 3.0 peak at 150-200MB/s although it has a theoretical speed of 5Gbps (625MB/s), thus just as USB 2.0 its only at 1/3 its speed.

The reason is very simple why USB 3 even have difficulty outperforming SATA 3Gbps. True eSATAp (eSATA/USB) is just a simple external bracket for the onboard SATA + USB connector, there is virtually no translation required.

USB always have problem with memory and cpu overheads. The original USB 2.0 promised 60MB/s but in reality it is only 20MB/s (1/3).

eSATAp will always have the advantage due to SATA being the default connector for all HDD/SSD and optical drives.

Even when Intel Light Peak is out, eSATAp will still be around, but USB 3.0 is subjective taking into consideration the additional cost or an additional chip set to implement this technology.

USB was able to win the war against Firewire IEEE 1394 (found on Apple Macintosh) due to its better marketing strategy.

That doesn’t mean USB is better than FireWire.