I shoot with an NMLRA Field Rep in our White River Brigade and he uses
the teflon coated patches. His are pillow ticking patches, and they have
that same greenish coating that is shown in the link you posted Roundball.
Now I don't know if they are coated on both sides or not, but I do know that he gets some mighty fine groups using the teflon coated patching.
They must work as I heard on the radio today that he won a bronze medal
in the State "Cornhusker" games, in Lincoln, NE for the 100 yard offhand
rifle match, and he won gold in those same games with 25 & 50 yard pistol...
So,,, I'd say they are worth a try if for nothing more then to answer your
own questions about them. Who knows, you may really like 'em?