I don't see what these stories are meant to prove... in 2002, I bought two Dells, they were 100% glitch free. In 2006, I replaced them with two new Dells, one (the desktop) was glitch free, the laptop's battery died prematurely. Called Dell, they stopped by the next day with a fresh battery covered by the warranty. I'm typing on that machine now.
In 2008, I bought an iMac. Exactly one year later, it died, and by died I mean when you press the power button you hear a faint whirring from the Superdrive that stops after 10 seconds, but the screen remains pitch black, there's no Apple startup sound, and none of the fallback methods like SMC reset or boot from OS DVD does squat. On the false assumption that I paid through my nose for AppleCare to get on-site repairs like with Dell, I called AppleCare and they explained that they're too aloof to bother with petty repairs, so I have to drag the damn thing to the nearest service center (60 miles away), therefore the iMac has been sitting in my "mañana corner" for about a month now. Ironically, my Dell desktop which had remained glitch free for 3 years, died only 2 days later. But Dell came over and replaced the motherboard the next day so the downtime was less than 24 hours.
What does this say about Dell machines, or Macs, or anything really? Nothing. It's just one man's story. The next guy can have 10 broken Macs out of 10, the next after that can have a 20-year history of glitch-free Macs... that's life.