@ LSD :D I was more refering earlier to realtime preview in OpenGL with textures included, and I took your castle model for example, just to explain problem better (OK, make it 2 milion polycount in Rhino and then play with it in OpenGL :P)... You were saying that you are getting 50 fps with model which has 300000 polys or something :P As you proly know, physical limit your graphics card has is about 30 milion triangles/sec, that would be like 600000 per frame (far less than our average Bryce scene is, wouldn't you agree). If U are having OpenGL preview with textures involved (your model is 30Mb already, for example) I can clearly see how 64 Mb of memory on the video card can be a serious limit :D Another thing is (refering to a scene size) that Bryce saves everything in one portable file (textures included) and all the models are saved as triangles (which doubles any quad geometry, this tesselation happens on import) so if your OBJ model was 30mb, Bryce is gonna save it as 60 (most annoying feature of Bryce rendering engine is that it cannot see beyond triangle)... Anyways, nice discussion, indeed :D