If you pay $80.00 for the system. Each purchase will do 4 barrel treatments. Treatments have to be reapplied every 100 rounds or so. If we then figure that a purchase is good for 400 rounds and costs $80.00, then 4 treatments will cost $320.00 and be good for 1600 rounds.
I'm trying to figure out the real savings rather than just getting a new barrel for $300.00. Of course, you have to pay for installation of the barrel if you aren't equipped to install it yourself. If it is true that continued application will STOP barrel erosion, then I suppose it is cost effective.
I would be really interested to see a controlled study on two identical barrels being fired with identical ammo. One barrel treated per manufacturer recommendations, and the other barrel untreated. Then use a bore scope and bullet depth seater gauge to find out when the beginning of the rifling has eroded forward by .002 or any other pre-determined distance.
Then we would be able to tell exactly how well (or not) this system works with the caliber used. For commonality, I would suggest using either 223, or 308 for the testing.