OWC Dual-drive Enclosures Overview
In December 2010, NewerTech released their new Guardian MAXimus Mini and OWC released the OWC Mercury Elite-AL Pro Dual Mini enclosures. In this article, I’ll refer to these together as the Dual Minis.
The Dual Minis are “quad interface” units, which means that they can be connected as follows:
- eSATA (fastest by far);
- Firewire 800 (reasonably fast);
- Firewire 400 (slow);
- USB (slower than Firewire 400).
The eSATA option is a possibility on the Mac Pro, certain models of the MacBook Pro, and a 2010 iMac modified by OWC to have an eSATA port. For the fastest external performance, use eSATA.
Dual drives inside
The Dual Minis take any standard 2.5" laptop hard drives or solid state drives. Since there are two internal drives in one Mini, the following options are available:
- RAID-1 mirror (redundancy, tolerates a drive failure);
- RAID-0 stripe (higher performance, failure of either drive loses all).
The drives should be matched in size and brand. Though mismatched drives will likely work well enough, I can’t recommend that approach. My advice is to buy the units pre-configured with matching drives, and if capacity and budget allows, prefer quality solid state drives.
Not just for portable use
Although these Dual Mini offerings might at first glance seem oriented towards laptop use, they are so nicely compact and offer such good performance and relative quiet, that users of desktop Macs will also find them very appealing.
The most compelling application for the Dual Minis is as a RAID-1 mirror, because portability entails a greater risk of shock and vibration which could kill a drive. Of course, dropping the unit on the sidewalk has a good chance of killing both hard drives, so the professional photographer or videographer really should be using solid state drives for critical work, not hard drives.
Unless you must have the additional space or performance, I strongly recommend using RAID-1 with these Dual Minis.
- Any storage application for which high reliability is desired, e.g., an always-on music library or video capture (use RAID-1 mirror mode);
- Critical data (use RAID-1 mirror mode);
- Data backup when traveling with a laptop;
- Compact backup for storage offsite eg in a safe deposit box;
- A boot drive, so that the internal drive(s) can be use exclusively for data;
- A mirrored clone for a backup of any of your internal drives;
- Transferring files conveniently from one Mac to another.