8GB is likely more than you'll ever need, and you can always upgrade it later if you want to, as it comes with 1x 8 GB dimm.
A second 8GB DDR3 1600 dimm is $68: »
www.newegg.com/Product/P ··· 20313298What is NOT upgradeable is the GTX 870M, which is considerably faster than the GTX 860M in the other offerings people have posted. I would go with the XoticPC build for that reason alone.
Then, if you really want to turbo-charge your computer, you get the following upgrades:
• Second 8GB ram dimm - $68 (link above)
• 250GB mSATA drive - $160 - »
www.newegg.com/Product/P ··· 20147316This doubles your ram to 16 GB and gives you a 250 GB SSD boot drive while keeping the 1 TB HDD in its bay. All you have to do is use a program like Acronis to flash the OS to the SSD.
Points where I would splurge on the XoticPC build, if possible:
• upgrade GPU from Nvidia GTX 870M to Radeon M290X - $75 (incremental step up)
• Copper Cooling upgrade - $79 (cooling is ALWAYS an issue with laptops, and moreso with gaming laptops, so I'd consider this a worthwhile investment)
Understandably, this will run you over budget, but I just wanted to throw these two possible upgrades for your consideration. Anything else upgraded through the manufacturer is likely a wash.
I would NOT select the following:
• Any of the overclocking options, this will almost always reduce the life of the laptop and make it run hotter