What are you going to be using the laptop for Oakesy?
Alienware machines look really good and are intended for gamers AFAIK. The spec you quoted should be good to run almost any software you can think of for a good while!
When specifying laptops for businesses I always go for big brands (Toshiba, Sony, Panasonic, Samsung etc.) because, should anything bad happen, replacement parts tend to be available for a long while after the sale is made. I have had some bad experiences with lesser "brands" - parts are often unavailable even months after a sale. A three year warranty is always useful, but make sure that it is insurance-backed just in case the company folds.