The lens hood, very strangely, attaches to the barrel in such a way that it does not extend with the front element when zooming or focusing. The macro mode locks the lens at 80mm & allows a far larger throw for focusing, so it´s easy to manually focus in macro mode. The lens auto-focuses fast because the throw is so small, but that makes it very difficult to manually focus. I don´t know if there are optical or other differences.
I have the version two which has a metal fitting rather than plastic so it´s probably more robust than the others reviewed here. I paid €29 for this lens so it was certainly a bargain. Bad lens hood, difficult to manually focus