I own an ACOM DATA external 120GB USB 2.0/Firewire hard drive. It has been extremely durable -- my biggest complaint is kernel panics, they happen about once every month or 2 when plugging in/unplugging the hard drive. I back up about once every 2 to 3 days on average and use the SuperDuper! shareware application. It is hard to believe that SuperDuper! lets you do what you can do for free and unlimitedly.