Truthfully I'm not sure as I haven't play Guild Wars 2. I have the i7 3630QM but I'd imagine it'd run GW2 at a mix of Good-High settings.
Ive been shopping around and i think i may go with http://www.ibuypower.com/Store/Batta..._Gaming_Laptop slightyly different then the above, but has a 17 inch screen. I need a laptop for college and for general gaming so its the best ive found for under 1200 so far.
From the link you supplied 2x8GB is the same price as 2x4GB, you likely won't need the extra 8GB but more RAM never hurts especially if you are doubling it for the same price other than that the system should be fine.