Hi Max

Your models are good, but on all the curved surfaces i see the tell tale signs of polygon mesh and not NURBs clean curvatures, unless of course you modelled them that way. If you are more comfortable with OBJ that's fine, may I recommend you adjust the "Divide larger than" to produce a greater mesh density. Weld edges and, if you are only exporting to Keyshot then use Triangles only as KS will triangulate your mesh on import if it's a non triangular one anyway, so better to do it with MoI where at least you have some control over it.

Martin Spencer-Ford