Thank you all, these are great infos! I guess i have been doing just like you Guy, i import and process in my internal hdd, then immediately export the files into an external (usb, yes, i know, so slow) hdd and keep the lightroom catalog + cache in the internal hdd. I don't really understand what is a sataII, is it a hdd? What you get from apple isn't the best hdd ( spining drive) available? Buying a ssd is a bit too hot for me now since i dont want less than 200gb so what do you mean Guy when you said " get a sata II later?" Sorry i'm a bit confused here. Another question: with my last laptop i did buy the ram 3rd party but now with the unibody you can still open the laptop and replace the ram?