Many of the long armers in our quilt guild are saying they use this pen on their own quilts and are very happy with the result. I think you should ALWAYS TEST any markng product on your fabric (a scrap) before using it to mark quilting lines. But because of my friends' good result, I will be using one of these pens to mark a quilt for quilting this week. I am actually quite excited, as I do NOT like the pounce thingys that I cannot get to work (even after coaching! :shock: ) and I don't like the lines I get with the soft quilting pencils. Anyway, I'll let you know! :thumbup: