Yeah I have used it, very time consuming though. But definitely one of the better ones out there as you can literally model anything.
Please try Flora 3D it is much fast and very easy, but there is no link for it, aNYBODY HAS ALINK PLZ POST IT HERE FOR THE LATEST VERSION.
Flora 3D is very simple. If you have 3d max there is a free 3d script that does trees as well. Might as well list every product going.