I too experienced significant failure with newer Maxtor 7200rpm HDD. A DiamondMax 60+ failed within 3 months and the replacement DiamondMax 45+ failed within a day with SMART error (I suspect it was a bad RMA drive from someone else). This was eventually replaced with a Barracuda III and has worked well since.
The case has housed 2 other 5400 rpm IBM Deskstar 5 and Quantum Fireball CR disks. They are both 2 - 3+ years old and I have had any problem. Power supply in Enermax with twin fans.
My own theory is 7200 rpm drives are not easy to make them reliable with prices dropping like leaded balloon. You get what you pay for is very true here for HDD. This is real unfortunate as HDD is the most important asset in a computer system! I really miss those old reliable HDD that works for years without even a bad sector.