Twenty freaking percent? Judging from the sound of your name, your company is none other then the Italian Mafia

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Jokes
The HP ZD8000 looks sweet, but have you considered the Sager 9860. If your going to get 20% of, you might as well go for the top performer. Also, I suggest that if your going to get 20% of anyway, that you wait for an appropriate time when Dell gives away something like a $600 rebate of selected laptop systems (This happens from time to time). $600 coupled in with a 20% discount will save you a significant amount of money.
Think of it this way, if you work for the Italian Mafia,

and I'm sure you do, the XPS goes well with all the killings since it has a huge skull on top of the LCD lid.