Installed it last night. Works fine. To the guy that said that he is going to laugh if we have to re-install our systems when the final update comes out, a few of us have installed 4l5 and 4l7 and there were no problems which leads me to believe that since these are all versions of 10.0.1, and we keep installing them with no probs, then when the final comes out, it should work just the same. Still no noticable speed increases. Though I do like the ability to install 2 things at a time. When you get the 4l5 and 4l7, it comes with a few diff pkg installers and you can run them at the same time. Very nice.