I'm afraid you'll have to question this further...
Final vertex count depends heavily on the shading model used (flat, smooth), how you send your data to the graphics card (triangle strips, fans, indexed lists, etc), what you want to with the normals, how you have your uv's set-up, if you batch render by material, use limited file formats in the pipeline and so on..
While necessary for the cube (sharp corners), in the sphere's case Esenthel does come up with redundant vertices - which can be easily fixed in v1, but not so in v2 :(
-edit: the above picture and comment is talking about ms3d import, if I import the fbx version of the sphere the results are different (151 vtx, 224 tris) , also if i import a .obj (151 vtx, 32 tris, 96 quad) ... depending on the app exporting it, and various options selected at the time.. but ms3d importer does seem to produce higher than really needed vertex counts