I'm considering my first Mac and have been checking the specs. I shall go for the base model 27" i5 3.4GHz 8GB model. I note the specs for this give the max memory of 32GB whereas the higher models say 64GB. Has the base model been shackled in some way? I don't expect to need more than this anyway but am just a bit curious. Have Apple also restricted any form of processor upgrade from the base model?