I have read how in theory USB 3.0 have much higher bandwidth (5Gbps) vs eSATA 2.0 (3Gbps)

I have also read some tests which suggest in the real world this is not true: so I tried to buy a new drive to test it out.

Transfer: 3GB single file
Computer: i7 laptop with 280MBps (R/W) SSD

1)
eSATA Toshiba 500GB 7200rpm drive to transfer file to SSD: burst speed of 180MBps then slows down to 90MBps
 
SSD to eSATA: burst speed of 160MBps then slows down to 90MBps


2)
USB 3.0 Toshiba 1TB 5400rpm drive to receive file from SSD: burst speed to 220MBps for 1 sec then slows down to 30MBps and at the end of copying had to wait 30 sec to complete file transfer

USB 3 to transfer file to SSD: constant rate of 30MBps


Now i know this is hardly scientific as the hard disks are different BUT the new USB3 drive has no way to let me open and swap the disks so I can't put the 7200rpm disk in it. 

I'm sticking to eSATA despite needing to plug 2 cables in (one for data one for power). THere are newer eSATA devices that only require one cable. My advise is buy those and NOT the USB3 drives.