Unless the size of the screen is an absolute deal breaker for you, get the Alienware m11x r1.
Dell is always trying to unload these since they released the r2 model with the i-cores so they always float around $600, less on days like Black Friday and you can get discounts through Dell University or Dell EPP sometimes.
Use the savings to upgrade to an SSD (replacement of parts is covered by the Alienware specific warranty). I think the best thing you can do to make a laptop perform better relative to what you would want out of a laptop, especially an ultraportable, is to upgrade to an SSD.
http://www.newegg.com/Product/Produc...-542-_-Product
You end up with an SSD and a better graphics card. You can shell out the $40-50 for upgraded ram through Dell itself, or since you're replacing the HDD anyway order 4gb from Newegg for $40 and Craigslist the 2gb that come with the laptop.