I just bought one today off UsedMac so I don't have it yet but I did configure it with 6GB of RAM instead of 2GB on their website. Question, am I able to upgrade the CPU or video card any at all? Also it comes with a 320GB HDD and will probably want to upgrade that with an SSD, is there a max size this can handle? This is my first Mac since I sold a G4 years ago so I am excited and want it to purr with Yosemite (if possible, if not I will just stick with Mavericks I guess). Thanks in advance!