Either one will work well. Nice things about soda is it helps with the burnt smell and if you have good windows in the blast area you won't etch them with over spray.
However, this is assuming your pot is set up well for blasting soda, a good metering valve a sharp 60% bottom and good water separation. It cost more but I tend to get a lot more time from a bag of soda than I do with glass. If you are renting a general purpose blast pot that you are not experienced with you may do better with glass.
However, this is assuming your pot is set up well for blasting soda, a good metering valve a sharp 60% bottom and good water separation. It cost more but I tend to get a lot more time from a bag of soda than I do with glass. If you are renting a general purpose blast pot that you are not experienced with you may do better with glass.