I guess a lot would depend on the specs of the Windows 8 tablet; such devices may not have a graphics chip powerful enough to do 3D work and process speed is also important. At one time I really craved a Windows tablet so that I could use Corel Painter on it and draw and paint directly on the screen.  Since then I purchased all sorts of art apps for the iPad and found that I still prefer to do such activities my desktop computer with my Wacom Tablet, on the iPad my fingers block my view and it's easy to make marks unintentionally.  I don't know what advantages, if any, working with Poser on a tablet would be be--other than portability.  I do get that some artists like to use their tablets and smart phones as portable sketchbooks.