Hi Orhan, you'll get the best information if you test each one yourself. You can get the MoI v3 30-day trial version from the downloads section of http://moi3d.com . There are a lot of improvements coming for MoI v4 though which will be out before the end of this year. V3 does have the ability to generate high quality n-gon meshes instead of only triangle meshes though. Test it by opening up your stp file and then doing a SaveAs to .obj format, then load the .obj file into Cinema4D.

- Michael