Why the correct grade of abrasive will work harder for you.
Here's the comparison between Blast-One Garnet and an Imported Grade Abrasive:
With Blast-One Garnet the blast stream can carry 4 times the quantity of garnet grains, each carrying tremendous kinetic cleaning power. The smaller grains also scour out deep into the pits and leave a cleaner surface, faster.
With imported coarse abrasive it is very hard to clean out the pits without using a lot of abrasive.
Blast-One Garnet is proven world-wide to be just the right size mix to clean off the heavy rust and to also clean out the deepest pits.
Imported coarse abrasive means you have to open the valves up more to let it through and use more abrasive each hour.
You should also ask yourself "How much Abrasive should you use each hour?"