For Mac owners considering an upgrade to an SSD [Solid State Drive], the OWC Mercury Extreme Pro RE SSD is a great choice, thanks to its GC abilities. Some day almost all computer drives will be SSDs, but that scenario is a ways off as SSD drives are still VERY pricey compared to hard disk drives (HDDs).

That said, SSDs do have advantages over HHDs. They offer faster data access (they don’t have to spin up the drive platter or move drive heads), use less power (there’s no power draw for the motors) and higher reliability (SSDs store all their data in memory chips, so there are few moving parts to be damaged). Despite these benefits SSDs won’t become the norm until: the price drops and their capacity gets closer to that of SSDs. (The OWC Mercury Extreme Pro RE SSD I reviewed was 100GB and costs about US$400.)

But if you want/need/gotta have a SSD for your Mac, the OWC Mercury Extreme Pro RE (the RE stand for “Raid-Ready Enhanced) is for you (and it’s five-year warranty helps alleviate the pain of the price tag — well, a little). The drive also has an over provisioning rating of 28%, one of the best in the business.  Over provisioning is a term used to describe how much excess/free capacity are available compared to used-capacity. OWC uses it in its SSD line to fine tune the Garbage Collection (GC) abilities — a form of automatic memory management — of the drive for Mac systems and maintain peak performance throughout the life of the drive. 

The OWC Mercury Extreme Pro RE SSD is housed in a brushed aluminum casing with smooth edges and a blue paint job. It’s relatively easy to swap it with any 2.5-inch SATA form factor drive. Though it’s a 100GB drive, it actually contains a total of 128GB NAND flash memory; however, 28GB is reserved for the aforementioned over provisioning and unavailable to you.

The Mercury Pro family uses DuraWrite wear-leveling and block management technologies to keep read/write performance at a peak. So how fast is the OWC SSD? Darned fast. But let me refer you to the specs at the Mac Performance Guide (

° “Reads speeds matching the best speeds available, and the highest write speeds I’ve yet seen with a Solid State Drive;

° “Write speeds that show no degradation in my initial “seasoning” and moderate abuse, whereas other brands show drops of 15-20% after a single DiskTester fill-volume. Yet the OWC Mercury Extreme SSD write speeds are much than the other two brands I’ve tested, and stay there, no small matter.

° “Sustained write speeds of 260MB/sec and read speeds up to 280MB/sec with no sign of degradation. That’s nearly as fast as the 3Gb SATA 2.x interface allows.

° “Photoshop CS4 scratch volume performance in a 2-drive RAID setup that is the fastest I’ve yet observed, blowing away my previous champion, 4 X 2TB RAID-0 hard drives.”

So if you want a drive that’s fast, fast, fast, this is your baby. That is, if you have the cash, cash, cash.

For more info on the OWC Mercury Extreme Pro RE SSD, go to .

Rating: 8 out of 10

— Dennis Sellers