As a volunteer beta tester, I donated my services before the public release of TTP 4.0.3 and there's a great deal this utility does and does well.

I just launched the application and here's a partial list of tests, repairs and procedures.

Hardware Tests: Cache, Clock, FireWire, Main Memory, Mathematics, Network, Processor, USB, Video Memory

Drive Tests: Disk Controller, Read Write, S.M.A.R.T., Surface Scan

Volume: Tests and Repairs Volume Structure

Files: 1. Tests Files 2. Tests and Repairs Finder Info

It also does Directory Maintenance (Micromat's equivalent of Alsoft's DiskWarrior "Rebuild Directory," and a whole bunch of other things.

On G4, I have it programmed to do SMART testing and automatic diagnostics of Volume Structure (they recommend half-hourly or hourly checks (I can't remember), but I just have it check both every 24 hours. And if it finds any problems, I gave it an email address to which to send me alerts. But because I clone my volumes on a regular rotation basis, I don't use the "Protection" feature that maintains invisible files of volume structure.

I have no affiliation whatsoever with Micromat other than as an unpaid volunteer beta tester, but--as is obvious--I've found TechTool Pro a must-have utility.

Respectfully, Norm

I'm with most of the folks. I got a second TTP4 license
for Leslye's machine (not horribly expensive to add
licenses), set up both to run off eDrive, and don't
see any terrible slowness. And it's a great product.

If their comparison is off on so basic an item as price (see DiskWarrior, which lists for $80), I wonder if they're off in other areas as well? That said, I think trying to compare any of these products with DW is counter-productive. It has never been advertised as an all-encompassing disk utility. It only does one thing, but does it far better than anything else on the market.

If they would like me to review it for inclusion in the OS X Forum FAQ, I'd be happy to accept a gratis copy of Drive Genius.

G