Dell Aus business support is very good
As it is everywhere else. This is the key though..
Dell systems are as good as the market they are targetting.
If you're going to buy Dell, or Gateway or Compaq, etc.. the business-grade workstations will always run better than the home-user desktops. At least that's been the case in my experience.
From their point of view, business machines have to be more reliable as they represent a different and far more visible impact to their bottom line. (Dell can afford to @#!* you off, but can't afford to @#!* off an office buying 30-40 of their business class PCs every quarter)
They are always more expensive, but that's the price of reliability... Of course, there will be the roaming exception to that rule, but in general, that's been the consensus in my experience.
Rule of thumb..
consumer class PCs = crap.
Business class = More reliable with the occasional crap.