I love this set of templates. They are all very useful size-wise but my favorite part is that the 'innie' and 'outie' curves produce the same size Quilted arc so you don't have to be a contortionist to use them! Just switch the side of the template to quilt the other side of the arc.

This set is invaluable in my ruler quilting. I can combine these with other "flower" designs to embellish around the circle from petal to petal. I can use them in borders. I have used them in all over designs in blocks. The varied sizes was a huge buying point for me since I have practically every size I will ever need after buying this set.