Let me re-phrase - building your own is perfect, so long as you are not on a budget and know what you are doing. For the avg. pute user, this won't apply (or those with wives that just won't let them toy around ). The avg user is gonna be using something that's on par with most store/internet bought machines. Whether they build or buy.
Of course the twinkers could build an uber machine. But who has that money or the time? I'm sure some do, but most don't. But a twinker could build a better machine for the money than buying one.
So you live with what you can get. I myself think Dell has a very structurally sound architecture. They use solid, quality materials in building their systems. Maybe not the best; but far from the worst. And there is a lot to be said for the support side of it.
Most people could not build a system that is stable for less than what they could buy it from Dell or a competitor. A lot of factors go into building your own. Takes some skill to custom build. That's always a factor.
Dunno, for those of you that read this and fear self-builds, you can't go wrong with a Dell. It'll take some software adjustments once you get it, but the hardware is sound and reliable. As for HP, Sony, Gateway, Compaq, and a slew of others, good luck. I've had pretty extensive experience with the four above and would recommend none of them.
Wow, i sound like a commercial