I just want to say in my (too many years) experience, on the occassions I have had to RMA Maxtor, WD or Seagate, I have gotten new drives.
I would add that 95% of the failures I have seen occured during burn-in. In my experiecce drive failures are due to manufacturing defects, shipping defects or defects in the surrounding hardware and you see this almost immediately. Yes drives like other components, can fail at three years, but I find this very very rare.
I would add that my worst warranty experiences have been, and don't flame me, with Seagate. This was with a failure at eight months, which in my expeirence is rare. Despite their announced five year warranty, clearly applicable on this drive, they made me spend a crazy amount of time after refusing me based on manufacture instead of sale date. The purchase was eight months before from an authorized retailer.
Again, I wish to contest the idea that refurb is the norm. In 15 years or so I have ocassion to RMA perhaps a dozen drives out of 300-400. I would say ten of those failures occured in the first days or month. We RMA's a failed Maxtor last month and the replacement was a new unit. I do not recall ever getting a refurb except from seagate.
I would also say a lot of the hype on warranties, especially long ones, is misplaced. I have yet ever to have worked with an IT department that would send in a drive after a year. prices fall too quickly to bother. You've cracked the case. To pay to package, mail and wait, in order to install a three-year-old model, or even last year's model, is non cost effective in the extreme. Just look at hdd costs today: $0.30 to $0.25 gig. The 40 gig you bought three years ago is worth $10. to open the case, box it up, fill out the RMA and pay to ship it, in order to go through the labor of reinstalling 40 gb back in -- is something no one in their right mind does.
Lastly a lot of what one reads is prurely anecdotal. People become imprinted and fierce haters of one brand or another due to a failure. In fact averaged MTBF data, when properly parsed, average out shockingly consistantly between manufactures. Look at deskstars, they are actually more reliable and have higher MTBF than average. But with the deathstar episode, which arose from the combination of bad firmware in a very very short run (six weeks or something like 0.012% of all deskstars made) combined with a bad response from the company, earned a extremly reliable line of drives a bad reputation amoung amatuers. We buy them all the time now and have no trouble.
My advice. Run the hdd through some good rigorous diagnostics when you install it (please this is easy and can be done unattended). If there is a wiff of a problem return it to your supplier or if retail, your retail vendor for a new replacement.