For the same price is it worth it to get the base retina macbook pro or the loaded 13 air with 512 ssd i7 8gb ram? cause I really dont need 512 just need 256 but 512 would be nice....so am i better off for the same money getting a 15 retina base? cause to me that machine is basically the 15 air everyone always rumored about n well even though I dont ever do anything with graphics, im a used car dealer and do a lot of web stuff and upload pics of cars, I bet the retina would be nice... any thoughts?