Chez, discussed earlier
here, those places I mentioned back up their systems with good warranties and supports. Between AW and Voodoo, the difference is, you pay Voodoo extra to test, benchmark, and optimize systems for over 72 hours, and if anything goes wrong, you can get help almost right away. I'd not even compare Voodoo with AW, it should be Voodoo vs Falcon NW.
AVOID: all major brands, check their ratings here, you pay a premium to get support/services catered to budget systems, also any builders with substantial feedbacks and score below 8 (that includes Alienware).