Pilou: Thanks:-) The rendering took around 15 minutes, mostly because I went a bit overboard on soft shadows and such. I guess the settings could be tuned to render in about half that time without too much notable quality loss.

Michael: Yeah, MoI is great for these kinds of objects. Doing this in a poly-modeller would have either taken too long, or resulted in a "messy" object. XSI handles n-gons in .obj files quite well, there's only two situations I can think of where they'd be a problem. If for some reason you'd need to smooth the object further, both the Catmull-Clark and the Doo-Sabin algorithms will lead to slightly warped texture coordinates on n-gons. And, if you want to deform the objects in animation, large n-gons such as end-caps etc. can lead to some triangulation popping in resulting non-planar n-gons.