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MacBook Pro eSATA with OWC QX2 RAID-5 Enclosure
The 8TB OWC QX2 enclosure in RAID-5 mode (striping + parity) was used for this test. In RAID-5 mode, its capacity is 6TB of usable storage, and it can tolerate failure of one of the four hard drives while continuing to operate. See the review.
Performance of the QX2 represents the fastest possible results you’ll get with eSATA on the MacBook Pro with any external hard-drive based enclosure, though dual-drive striped enclosures should offer similar performance.
Read performance is fast with the OWC Slim and the Sonnet Pro, but lags with the Sonnet Edge. (On the Mac Pro with an appropriate SATA card, read performance is typicall ~200MB/sec with the QX2 and certain SATA cards).
Write performance has always been impaired with eSATA through the MBP ExpressCard/34 slot, and runs here at about 60% of the potential speed seen on a Mac Pro. The Sonnet Edge lags the other two cards.