I made a quilt for Project Linus using Jenny's Churn dash pinwheel tutorial as well. As long as you use a sashing between the blocks, you should be fine. I wouldn't make these blocks and attempt to sew the blocks directly together with the bias edges.
When I made mine, my inner OCD Quilter came out and had to trim down the initial pinwheel blocks to be a size that was easily divisible by 3. I cut my 10" blocks cut from yardage. My initial pinwheels measured about 12.5". I trimmed them down to 12" so that I could make nice easy 4" cuts.
These blocks turn out so cute and I enjoyed making them.