I'm not even sure the prebuilt Dell route is going to provide a better experience. Sure, you get a warranty and one manufacturer to deal with, but it's still a hassle when the components keep failing.

Over the years, I've watched the following Dell systems just fall apart:
1. A friends Inspiron 5150 laptop from a few years ago. It was so bad, Dell lost a class action lawsuit about it. Of course, the lawsuit was well after my friend had junked the system due to being unreliable.
2. Multiple Dell Inspiron 9100 laptops owned by myself and friends. Every single one of them had at least one failed power supply. Beyond that, I had a bad IDE controller, one had bad memory, and one failed both a graphics card and the hard drive.
3. Too many to count Dell XPS desktops needing motherboard replacements. Various models of the 600 and 700 series have just failed to work under a development workflow. SATA speeds are so horrible, a Velociraptor performed just as badly as the stock hard drives. It's bad enough that I know two companies that have dumped them and bought the Precision workstations.
4. Dell XPS laptops, M1300 series. Also saw plenty of these fail, though this time it's NVidia's fault with their bad GPUs. Vista also didn't help the situation, because when the GPUs weren't busy failing, wireless networking was horribly unreliable. XP on the same hardware worked fine.

I think the race to the bottom in general has really hurt the industry as a whole.