EFD Software's HD Tune is described on the company's web site as such: "HD Tune is a hard disk utility with many functions. It can be used to measure the drive's performance, scan for errors, check the health status (S.M.A.R.T.), securely erase all data and much more." The latest version of the benchmark added temperature statistics and improved support for SSDs, among a few other updates and fixes.
The Plextor M6M 256GB drive offered competitive performance in HD Tunes' transfer tests, though it didn't lead the pack. Access times were quite good though, as were burst rates.
