not to mention there are limited choices for parts in your alienware PC. I've built a couple for fun (never bought em) and no matter what you do you always end up with at least 1 or two things that you don't want. The motherboard choise in particular is quite lame and restricted.
Yeah they run good sure. You can build much better, more customized rigs for cheaper. With the added fun of being competant enough to put it together. Not saying you paid someone an extra 2000$ to build it and ship it to you. XD