My setup at home is an Airport Extreme with External Hard drive that I'm using for Time Machine. A friend has asked me to help setup a backup solution for him. I think that duplicating my setup is the best idea, but wanted to check around to make sure I wasn't making a mistake. Is backup through the Time Capsule any faster than through a combination of Airport Extreme with USB External Drive? My setup has been great, but are there any other considerations I should make? Reliability? What is the maximum size HD that the Airport Extreme can support?