No I havent' seen them, but suspect they are jacketed bullet rounds. If so save your money and your rifle barrels. I've gotten a lot of feed back from customers about these and all say they rip out rifle throats like a wate hose wipes down a sand tower. Also, I know for a fact that jacketed bullets cannot lap the rifling eges or bottom of the grooves properly. In fact almost not at all, and this is mandatory to a good lap job. Better not do it than not do it right.
If you are only going to shoot jacketed, perhaps they would improove many barrels for jacketed bullet use only, if they are large at the muzzle as many are. If it didn't register clearly, I said PERHAPS. Which is to say, I still wouldn't try it.
To get a stright smooth bore finish by fire lapping I've found lead bullets the only good choice, and that with a hardness of about 12 bhn. Harder will not make the bore straight or as smooth. Softer requires a lot more shooting and tends to wear the throat faster than with 12 bhn.