Simmetry3d now has a companion visualisation product - WalkAbout3d. It is aimed firmly at SketchUp users and is designed to allow for real time walkthrough visualisation of SketchUp designs. It shares the same tried and tested visualisation engine as Simmetry3d, but there is virtually no learning curve making it ideal for SketchUp users who just want to experience their designs as real time walkthroughs

Check out the home page: