Unlike other types of blasting, soda blasting is much more controllable. Soda blasting can be controlled to the point that you can take off one layer of paint at a time. That's why it is the preferred method for removing graffiti. It is also perfect for removing rust from undercarriages from vehicles. Another reason it is a preferred method of rust removal is the soda acts as a natural rust inhibitor. It acts like a primer. If you sand blast or media blast you will leave exposed bare metal which then needs to primed and painted immediately. Soda blasting is very environmentally friendly and it costs about the same as sand and media blasting. The place I go to will do a whole undercarriage for about 75-100 bucks, depending on the size of the vehicle and the amount of rust that needs to be removed.