Looking for some suggestions. I am getting a WD Scorpio Blue 500gb for my early 2009 Macbook Pro. I am also looking to get a 1tb external for back up and extra storage. I was thinking about getting the Western Digital My Book Home Edition 1 TB but I also read some good things about the the LaCie Hard Disk 1 TB. Will I run into issues if the LaCie is 7200 and my Internal WD is 5400?