The vistapro picture will just be a background, but you can export vista dems to use in poser (or any other 3d program). If you use the imported dem then it will be a real landscape that poser figures can interact with. The dems can be exported at different resolutions so you don`t have to have a huge dem object in poser (unless you want one). If you add a texture to a low resolution exported dem it can look quite good.