First of all these are all the same computer with different names. They may be way less expensive than the EON18 but they don't come with as much accessories or customizable parts. If I were to choose though I would choose one of the ones that you showed me because of the price.
I know, that was the point of my post...... Like I said to Frozen, until they let you xfire 5870's the X8100 is the current king.
While you may not be able to paint the systems at the other places, you can add skins to them. And honestly, I don't think I would spend $160 on a paint job that is going to get scratched up anyway. If I were to do it and had the money to blow, I'd probably just bite the bullet and get a Falcon NW. (that's personal opinion though).
The only customizable parts the Eon has are the Quadro cards instead of the GeForce cards. The Eon also still has the option for Core2 CPUs as well, but most people are looking for i7s now. Not saying there aren't people who wouldn't still consider a Core2....
And yes, Eon lets you choose stuff like external monitors, keyboards and mice but you can probably find them cheaper on newegg.com or elsewhere.
Just so you know, I'm not trying to be a jerk or anything. Just playing devil's advocate.