I'm using a DIY PC for 6 years and I work with Dell computers
day in, day out at my client place where I am deploy to.
IMHO, Dell desktops rocks. (Desktops, laptop unless you are using
the high end series like Precision M60 and M70, don't even think of
buying other Dell series laptop, then of course it's my personal
opinion)
Why:
1) In terms of support they are very professional, they have all
the KB of their product. It's no nonsense support.
2) The price you are getting is worth every dollar and provides one
to one exchange on next business day basis.
3) Even if your desktop runs out of warranty, the support personnel
are still willing to help you out.
However there still Dell models that don't last more than 3 years,
the GX240 Optiplex series, most of them last for slightly more than
3 years because their IBM hard disk starts to give way after the 3
years period.
Even for home users I got several friends who happy with their Dell
products. Then again they might be the lucky one...