We use it all the time with ProE, no problems.
I convert the IDF-output in Mechanical Desktop to STEP or IGES format and then I put it into Inventor.
Coincidentally, we are running a short survey to get a better idea of ECAD-MCAD tools and data format usage. By taking the survey you'll see how you compare to the general industry once the survey is closed. You can find the survey at:
Welcome your feedback!