The theoretical maximum bandwidth of each common external interface are: USB 2.0: 480Mb/s;  USB 3.0: 5000Mb/s; eSATA: 3000Mb/s; SATA I: 1500Mb/S; SATA II: 3000Mb/s; SATA III: 6000Mb/s. The real transfer rate will depend on your devices.

Interface Bandwidth (Mbit/S) Speed (MB/s)
USB 2.0 480 60
USB 3.0 5000 500
eSATA 3G 3000 300
eSATA 6G 6000 600
SATA I 1500 150
SATA II 3000 300
SATA III 6000 600

RAID (redundant array of independent disks) is a data storage virtualization technology that combines multiple disk drive components into a logical unit for the purposes of data redundancy or performance improvement.

Please check if the drive is formated with FAT32, which can only allow a single file up to 4GB. If your file is larger than 4GB, then you have to re-formate the drive to NTFS.

JBOD ("just a bunch of disks")  is an architecture involving multiple hard drives, while making them accessible either as independent hard drives, or as a combined (spanned) single logical volume with no actual RAID functionality. Thus, JBOD can provide neither redundancy nor performance improvements. 

RAID  0  splits data evenly across two or more disks (striped) without  parity  information for speed. RAID  0 is normally used to increase performance. A RAID  0 can be created with disks of differing sizes, but the storage space added to the array by each disk is limited to the size of the smallest disk. For example, if a 100 GB disk is striped together with a 350 GB disk, the size of the array will be 200 GB (100 GB × 2).

An exact copy (or  mirror) of a set of data on two disks. Even one drive is malfunction, another drive keeps the whole data for redundancy.