There are 2 different product groups of CitySurf Family;
3D Flat System: This system is not an actual virtual globe (i.e., a sphere) server; it is a lite viewer for rendering a specific area of terrain like cities. Spatial data projections should be such as Lambert, UTM, TM for this type project.
Professional Globe System: Globe System displays and analyzes the whole earth in 3D. There is no restriction of any geographical region. Have enough disk space and data, you can view and analyze very fast with the Globe System.