I have been demoing the Bloc Loc Rulers for almost a year at local shops and shows. They are nice if you do a lot of HST. The cost is quite high. For HST the 6 1/2" size is the most versatile. The flying geese rulers they have are all size specific and I don't feel are worth the money. I'd rather do the no-waste flying geese method. The new rectangle rulers come in a package of 2 and I feel are the most versatile. There is even a book that goes with the new set. They bad thing is the cost. The new rectangle set is $40. I don't remember the cost of the book that you can use with the rulers. All that being said, it depends on the number of HST you make. The quilt Cinnamon Lodge by the creators of Bloc Loc is really cool but you can do it without their rulers. I do own the 6 1/2" square and I believe I have a smaller one, and although I do like the rulers, I don't make enough HST to warrant buying more and the cost is too high for my liking. I do own the new rectangle set and I feel I will get more use out of these, but I still feel the price is too high, but at least I can make more with the rectangle set (I also have the book too). I hope that helps.