I use the BP X-treme in 12, and the Polywad insert in 20.
I don't remember the shipping to have been that much. Maybe it was. Just order a bunch, you'll use them eventually.
The RXP20 seems to have been made just for the Polywad application.
I load 3/4oz spreaders with the standard CB 7/8 oz wad and a Polywad insert. International is peachy for that, I seem to recall 12.2 grains makes a 3/4 oz #9 spreader for use on skeet doubles in the left barrel of my Rizzini choked .018". It runs 1150 fps and works fine. It does make that barrel into skeet barrel. Fun!
For the 7/8 oz spread load I use the RXP20 and the Polywad disk. I favor the Remington hulls for this, stoked to 1200 FPS with 20/28 or WSF. #8 breaks the stupid close in wabbits, when I can get the gun to them.
You'll like the Polywad inserts.
