Can't say as I agree they last longer than any other computer.
Have a friend bought one of my homebuilt machines, tickled to death with it. Says it's the best computer he's ever had. A P4 3.4 O/C'd to 3.8. It's 6 years old. The 5.1 dolby surround speakers I sold him with it are 9 yrs old.
Still have a 7 yr old Dell here in the house.
Have another friend, gave their kid another of my homebuilt gaming rigs, still going strong, it's 8 yrs old.
2 of our 10 computers in the office are 9 yr old P3 1 Ghz HP machines. We bought 4 of them. The other two could have been fixed, one with just a new drive... but used it for an excuse to upgrade.
My newest machine is a HTPC running Win7.
My choice for my primary personal computing happens to be OS X.