OWC Mercury Extreme Pro RE 200GB SSD

OWC’s Mercury Extreme Pro RE SSD 200GB is a 2.5-inch solid-state internal drive. As with all solid-state drives (SSDs), the Mercury Extreme Pro RE SSD has no moving parts, a high price per gigabyte, and relatively low capacity when compared to standard hard drives. It does, however, offer a significant speed improvement over 2.5-inch hard drives and a five-year warranty. Our testing shows that after significant use, the OWC drive performs as well as it did out of the box—unlike some other SSDs.

To test the Mercury Extreme Pro RE SSD we installed it into a late 2008 Unibody MacBook with a 2.4GHz Core 2 Duo processor and 2GB of RAM. The system is not only ripe for an update, but the hard drive is also very easily accessible.

We ran a series of tests on the MacBook’s standard internal drive, a 5400-rpm, 2.5-inch Toshiba mechanism, to serve as a baseline before running the tests on the SSD drive. We also ran the same tests on a  7200-rpm, 320GB Western Digital Scorpio Black drive to serve as another point of reference—a faster drive than the standard internal, but much less expensive than an SSD.

Out of the box, we found the SSD to be, in a word, fast. It duplicated a 1GB folder 68 percent faster than the stock drive, uncompressed a 2GB file 47 percent faster, launched Photoshop 59 percent faster, and booted up 36 percent faster.

After hearing reports of performance degradation over time, we decided to run another set of tests using Mac Performance Guide’s DiskTester application. The application includes a Fill Disk test that, as its name implies, fills the target drive with small files until it reaches capacity. The application tracks the read and write speeds of the drive throughout the process and includes an average speed result at the end of the task. We ran this test and took note of the results, an impressive 255MBps reading and 173MBps writing. For comparison’s sake, a 7200-rpm Scorpio Black drive had an average read speed of 51MBps, and an average write speed of 62MBps.

We then followed a script used by Mac Performance Guide to “season” the drives by erasing, filling, erasing, cloning a system to it, erasing, filling and erasing the drive once more before installing our test system back on the drive and running the Fill Disk test again. While some SSDs in our testing did indeed suffer from dramatic performance degradation after the seasoning, the Mercury Extreme Pro RE maintained its same lightning-fast read and write times. The Scorpio Black drive also reported nearly identical results post seasoning.

SSDs have a finite number of times each block can be written to, so technologies like wear-leveling are important to keeping the drive performing well over time. The Mercury Extreme Pro RE uses over provisioning, setting aside 28 percent of the drive’s total capacity for maintenance like replacing bad blocks on the drive. Although this means considerably less user-accessible capacity, this over provisioning does seem to help maintain high performance over time.

Macworld’s buying advice

SSDs are not for everyone, at least not for now. Until prices come down and capacities go up, they will continue to be niche products meant only for enterprise servers and the most demanding power users. If you fit into that latter category, the Mercury Extreme Pro RE SSD offers eye-popping speed, as well as the peace of mind of consistent performance over time and a five-year limited warranty.

[James Galbraith is Macworld’s lab director.]