Again as with any tool in your 3d pipeline, you really should optimize the mesh for import.  Vue prefers triangles over quads, 1 tex layer per group and decimated to less than 100k polys.  It WILL accommodate a complex Poser figure non-optimized but it cant handle too many before your scene will crawl.  However if you optimize the figures as you would for a game engine, you can add many more figures to a Vue scene.  
If you use content from a lot of sources and need to a tool that offers the greatest level of flexibility and capability to optimize figures in your pipeline, consider using Ultimate Unwrap 3d by Brad Bolthouse.  Its brilliant. simple yet effective and its become the indispensable swiss army knife in my 3d toolkit.