I stopped using a GUI (SmartGit) when I encountered an error which was talking about stashes and something like {0}. I had no idea what the error was. Now I know how these tools work but I think that you can only use them effectively if you learn how they work and how the underlying system works. If you fail to do so you end up with a leaky abstraction which will at some point (and believe me it will) present you with an error message you don't understand and you end up with a problem you can't recover (yet). GUIs are fine but only if you know the ins and outs of the underlying system.