I had a client who needed to present a project of mine. eDrawings made sense and I knew the client had Macs. So I got them eDrawings for Mac. I hadn't used a Mac in years so it was a bit of a risk. Popped it onto the Mac's hard drive icon and up it came. eDrawings graphics on the Mac seem to be a bit better than on Windows. There also seems to be a wider range of formats to save out too. The client was impressed and may start using it to communicate between branches.
The only flaw, if there was one, was that the little "grabber" hand for moving parts did not have an icon, but was stuck in a menu. If you didn't know it was there you would miss it.