Just my .02 here but I would personally not use soda blasting. It is virtually impossible to get all the residue off of the car after blasting and if you don't get it all off you are headed for major problems. Again jsu my two cents worth, but you may want to do a search on here and mybe SPI site for soda blasting just to get an idea of what I am talking about. Best of luck with which ever way you choose to go.
Here a link to one thread about soda.. SODA Blasting