When I finish the output of what your export/import will be, check it out.
On the new map, it will be best to try and match the terrain up with your export. While this isn't critical as you can clean it up however you want (some clean up is going to be required most likely) the only thing that has to be matched up are mountains (to some extent). If you are exporting something that will end up with a sheer cliff face, unless you are planning on doing something with the cliff face, you need to embed it in an existing mountain on the new map.