I use a lot of strips for my quilts so my most used rulers are a 5'X24" Olipfa (love that edge), a 8 1/2" and a 12 1/2" square, and a 8 1/2" X 24" Omnigrid. I also use my 3 1/2", 4 1/2", 5 1/2", 6 1/2"and 9 1/2" squares frequently. Having the right rulers handy makes cutting and trimming much easier. I know I could probably do what I do with less rulers but I like to grab and cut without doing a bunch of figuring.