I am going to use Thangles for the units in part 1, my current project is made of pinwheels using the exact same size and I bought a couple of extra packs just in case. I love how the paper stabilizes that seam when sewing and pressing, I don't have nearly the warping issues I have had in past quilts with lots of HST. As much as I love Bonnie's Triangle tool, it is much faster to cut them out using the paper, too.