I'm in the process of saving up for the new 15 inch retina macbook, I'm about 500 dollars away from which model I want. I saw this deal on craigslist and was wondering if this is a good way to go or should I keep saving up for the rMacbook? I think its the 17inch from 2010. Are these things easy to upgrade? Like the RAM to 8, and put a SSD in it?