It's easy to see how these warranty assurances would appeal to drive manufacturers. The high level of engineering of hard drives have made them very reliable devices -- all things considered -- so the assurance easily fits the computer warranty requirements.

In fact, drives often live longer than the average lifespan of PCs. Disregarding the MTBF calculation, the average drive in real-world use lasts between 33,000 and 55,000 hours, or 3.8 and 6.3 years. That's with everyday, daylong use. In addition, the drives will last longer if they're turned off, which is often the case with desktop drives.

According to a ZDNet news story, an IBM spokeswoman said the company stood behind its three-year warranty, whether people wanted to use them "two hours a day or 24 hours a day."

So there's no worry about leaving your drives on. Mihalik said he leaves his running all the time except when he goes on a vacation.

After three or so years, you'll want to buy a new drive, anyway, since the new models will have two to three times the capacity. As mentioned in previous columns, desktop storage capacity keeps climbing. such as Maxtor's Personal Storage 3000XT, a 160 GB FireWire drive costing $399.95, show at the last Macworld Expo.

You Can't Always Get What You Want
From the outset, the whole 120GXP warranty commotion sounded like a lot of hooey. The claims went against everything I know of the history of the hard drive. After all, since the invention of hard disk storage in the mid-1950s, the entire engineering effort has been to make drives smaller, faster, and especially, more reliable.

Hard drives are amazing pieces of electrical and mechanical engineering -- their platters can spin at speeds up to 15,000 RPM while the magnetic read/write head assemblies flash across the disk surface, retrieving a single chunk of data in milliseconds.

I once had a field trip to a hard disk factory and watched them being made and tested. It's not the least bit like an automobile production line. No sparks or noise. The work is done in clean rooms with the workers wearing special antistatic suits and masks. Very impressive.

Still, any hard-drive manufacturer can have quality problems with a particular drive or a bad lot of mechanisms. For example, take IBM. A law firm recently filed a class-action complaint over quality issues with the Deskstar 75GXP; according to reports, this lawsuit may be expanded to cover other Deskstar models, including the 60GXP.

IBM has had a good reputation for reliability. I have a 60GXP in a FireWire enclosure and have had no problems. One prepress consultant I know would buy no others. However, his tune may have changed -- he didn't return my call to answer the question.

No doubt, this lawsuit, as well as the many reports of drive failures, must have exacerbated the online user community's concerns over the 120GXP warranty.

The medieval sage Maimonides offered this wisdom on the matter: "A man should be able to classify everything he believes so that he can say: 'This I believe because it is handed down from the Prophets; this I believe from the evidence of my senses; and this I believe from reason.' Whoever believes anything that does not fall within these three categories, to him apply the saying: 'The thoughtless believe every word.'

Perhaps it's a mark of our Internet age that every word becomes more believable. Even to the thoughtful.

Read more by David Morgenstern.