If you are planning on moving from one proprietary format to another, I would suggest moving your files to something that may be a bit more "universal" and able to be imported to the other program.
Sometimes, even when there is some ability to import other program's "working files", not everything translate well (not all the time, sometimes it depends on what version and what effects/features that were used in a particular file etc).
That's not to say that there aren't hiccups with a more "universal" format either, but I would say your odds are better then trying to import a proprietary format from another package directly. For cut work, typically wireframe info handles fairly well, at least in my experience, that may vary.
I usually for myself, have one master file that is the working file and then I try to have something that is the best that I can have while having more programs accept it (depending on the project and what was used, there are trade-offs this isn't perfect either). Mainly for this very reason, in case I switch to another program down the line (which I have done, numerous times depending on the program over the yrs).