I do not have any experience with having Apple replace a disk drive on the basis of a diagnosis from Checkmate, but when the TechTool Protection feature was unable to back up my disk directory because the disk directory contained one bad block, I brought my MacBook Pro Core 2 Duo to my local Apple Store, along with a screen capture of the results of the Surface Scan in TechTool Pro, and the drive was replaced under warranty.
The Apple genius was impressed with my documenation, and visibly relieved that I had both a backup of all of my data and a G4 Cube that I could use until a replacement drive could be sent and installed. We spent the rest of the appointment trading stories about people who think that backups are for other people. I never mentioned Micromat in any context other than using the software.
