I've been having recurring problems that Disk Utility, TechTool Pro, DisWarrior, and Apple Hardware Test have been unable to identify and address. So, I'm now considering a system reinstall. But I'm not clear what the best approach is. It seems that Erase & Install is more thorough than Archive & Install, yet they both seem to enable one to carry over all of one's folders, files, apps, prefs, etc.: A&I as the "archive" name suggests; E&I because it offers the option to use Migration Assistant. So how do they really differ, and when would the seemingly less-thorough one (A&I) be preferred over the other (E&I)?