It actually depends on how the authoring program exports. Not all file exports are equal - the OBJ export from Maya is different than the OBJ export from Silo. OBJ is usually the safest but it also creates huge files. 3DS is nice because it's about a quarter of the size of an OBJ. However, depending on export settings models can seemingly explode on import. Post back if this ever happens to you, there is a fix. They all write textures differently too (transparency being the biggest issue) Nothing is perfect but all formats usually come in pretty good. If the model surfaces are completely controled by texture maps, the import is great. It's just when textures are controlled by slider fucntions in their respective authoring programs that goofy stuff happens.