The question that you ask is not simple to answer. Is it a good business? Well obviously many have made it a good business and many have failed. I would highly recommend that you do not get into this field for the wrong reasons. If you go into it thinking that you are going to get rich quick or make some easy money, then it is not a good business. Medical billing is a complicated field and it is important that you know what you are doing.
On the other hand, it can be a great business. It is important that you understand that it is not simply data entry.
Michele