.obj files are the best for importing morph targets or props into Poser because a lot of freewares can optimize them and create excellent UV mapping to use in Poser. The main problem with .obj files is explained by "kruse" : an ASCII file (text) is always much bigger than a binary file like .3ds ... Moreover, a lot of 3d softs are unable to export a CLEAN .3ds format (even sometimes 3dsMax !!!). By the way, .3ds was the native format of (old' DOS) Autodesk 3dstudio.