I usually shy away from patterns that make you use their rulers and their methods. The tri recs tool is used in many patterns, so I would probably buy that one (with a coupon). The exception is that I did buy the Day and Night quilt book which comes with the ruler. It was worth it in that case, since the pattern gets 3 blocks of different sizes from the cuts. I make HST's and geese my way. As long as the end result is the same size, it works.