Okay, so I know they are similar but for one reason or another I can't decide. if you were buying an external hard drive for your 2007 Blackbook (late) what would you buy? http://www.amazon.com/gp/product/B001F9LY14/ref=noref?ie=UTF8&s=electronics http://www.amazon.com/Western-Digit...=dp_ob_title_ce?ie=UTF8&qid=1254686897&sr=1-1 http://www.amazon.com/Western-Digit...5000AN/dp/B001NANNNM/ref=cm_cr_pr_product_top They're all different, but none of them are different enough for me to decide. Is mac formatted worth buying over not? for a few extra bucks? Thanks.