Hey guys. I am contemplating purchasing the base model i5 21.5 or the 27 inch i5 refurb. My wife and I are going to use it as the home computer. I like the optical drive and the ram expanding option but I am concerned that the Sandy Bridge processor will be outdated and unable to run future versions of the Mac OS. Is this a reasonable concern? If so, I would stick with the 21.5. Also, we are planning on purchasing Applecare within the year of purchase with both models. If the 27 inch internals aren't outdated for a while, I would go with the 27. Thanks!