> Is an extra option (only quads) realistic ? I've no idea if this
> would be possible. I think it could be useful for further mesh
> deformation in other programs or for animation...

I don't think it is really feasible to get only quads and not ngons along trimmed areas.

I guess I can possibly imagine breaking things into a bunch of little slivery quads, but I think that would probably be about as bad as a bunch of triangles.

The underlying surfaces naturally decompose to quads, but this is interrupted where there are trim curves on the surface. There just isn't a way to get just simple quads when you've got a complex trim cutting into a quad... But ngons do work in these situations, because an ngon can hold the complex trim in one nice piece.

- Michael