What is the difference between 50/2.8 EX macro and 105/2.8EX Macro with Life Size Magnification?

The image of the subject, which is taken by both lenses, will have same magnification, however the size of backgrounds will be different. The picture, which is taken by 50mm/f2.8 EX Macro Lens, will have wider background if compared with the 105/f2.8 Macro Lens. Further, lens to subject distance will be different for making life size pictures with both lenses. The subject to lens distance for 50mm/f2.8 is 40.5mm/1.7in., however this distance is 120mm/4.7in., for 105/2.8EX lens.