I've got a 3yo Macbook and I want to purchase a portable external hard drive. nothing fancy, just something to back-up some documents and transfer my music and video files too. I was told that the LaCie Rugged 500GB was a good buy, but after looking at some reviews, I am a little uncertain. If this is a good purchase, that works, but don't want to get a lemon. Any help/advice is appreciated.