Also when you export to STL you may want to use the "Divide larger than" option in the export dialog to break down any larger polygons into a bit more regularly sized diced up pieces.

Here's an example of that type of thing:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2833.5

You don't want to go too overboard with this because if you dice it up too finely it will create an enormous file size. But if you have some polygons that are spanning a large percentage distance of the model (like on a broad flat surface portion) it can be good to get them diced up into somewhat smaller fragments.

- Michael