Hello, today I got my MacBook's RAM upgraded from 2GB to 5GB. (1GB+4GB) I was wondering if I should spend the extra $90 to upgrade to 8GB. (4GB+4GB) (I heard something about dual-channeling which I didn't fully understand...) I mainly use the Macbook for writing university reports and browsing the web. Really, the only "processor/graphic intense" applications I run is StarCraft 2. Thank you.!