"Will etch load over sarge with no issues? Anything special I need to do? "
Sure will. Just use the option to replace the existing filesystem, or whatever the wording is. You don't have anything you want to keep, do you? I was pretty intimidated by the "testing" thing, too, but it really does work fine. By the way, it's better to just use the netinstall or the businesscard install unless you have a connection issue during installation. You get the latest files in the first go.