I have done several PP projects. I am, however very cheap. I use regular printer paper for the foundations. When I sew them I do a quick reverse at the start and end to stop the unraveling when removing the paper and I shorten the stitch. Just before I go to remove the paper, I "fold" the paper on the stitch line and I rub a Q-tip dipped in water along the seam (let it sit for a minute or so). The paper comes off perfectly (usually) :-)