I have used SuperDuper for more than five years now. It has "saved my bacon" or that of someone I love at least once each year. SuperDuper is a breeze to use, with tons of safety, power and flexibility. Copy now or on any schedule you can imagine. What sets the product apart is what sets any product apart, customer service. I have never paid for an upgrade and, more importantly, the developer, Dave Nanian, makes it easy to send the information he needs to diagnose any problem and is back to you within a few short hours, often within a few short minutes. This is one of a handful of products I recommend highly and right away for all of my Mac friends. Between it and Time Machine, you are as bullet-proof as you can be.