[Henry Anthony]

I am a graphic designer who has experience with 3d animation programs. Learning Inventor to a level of expertise to design a competition robot took me about 40 hours and was a relatively easy transition. Basically, I just did the tutorials. One of our engineering mentors, a long time AutoCad user, suggested the team learn AutoCad. The kids were having a rough time of it. After a demo of Inventor, our long time AutoCad user said, "just use Inventor". Adaptivity and the fact that you could place a part in an idw that was fully dimensioned impressed him. So, not an exact answer to your question but having used neither product, I find Inventor to be far more user friendly. You might try the AutoDesk Inventor forums. This topic has been discussed there at length. I read the forums everyday - a very good way to learn. I almost never post a question as I feel the purpose of the forum is to support the professional user and I respect that.