I use edgecam and mostly inventor
2 options that work well for me.
1 is to dxf file out to edgecam. Edgecam opens them directly, no need to import, etc.
Only thing you may need to do is move it to get a correct origin, flop axis, etc. No biggie.
Edgecam also offers a direct module for inventor. Again you open inventor file directly, but advantage is if the inventor model changes, Edgecam will prompt you the next time you open the file and change the program to match. This option is an extra cost and I just got it, so have not figured it out fully yet, although I have seen it done, and it is slick.
Edgecam is probably one of the higher cost CAM packages, but I have no complaints about the software yet, and updates are done often.