I have the MacBook CD with the stock 60GB HDD and have been thinking about an upgrade. Recently I have been downloading a lot of TV shows (30GB so far... still have to get Lost season 3, OC, and others) and store it on an external drive. The largest HDD i could find was a 200GB but that was only 4200rpm, otherwise I would buy a 160GB 5400rpm one. Will it make a big difference, is 4200 considerably slower (the most extensive thing i do is recording in logic express, and i occasionaly use photoshop)?? Thanks, and if anyone can recommend cheap UK stores i will be very greatful.