Most of the manufacturers are using Pro-E due to its ability to integrate individual drawing data thru the whole assembly. Personally, I still use Autocad (mainly 2D, top view, 2 side views & an isometric), but that is how I learned & when the 3D products first came out none of my employers wanted to pay to have a design engineer learn to use it since that was the draftsmen's job. Now a young design engineer pretty much has to know how to use Pro-E.