I purchased every size they make. For me and my budget it was a big investment, and pondered a few months before I bought. For me, they are worth twice the money. I have tried many techniques to make half squares. For me, this is the best!!!! They are very accurate, they lock into the seam making squaring up very easy. I use HST a lot when making quilts with scraps. I don't think you will regret purchasing them.