When l quilted with a group in Fla., many members used the Frixon pens. I guess in Fla., it's warm enough, but here in Canada, ( or if you're in northern USA, don't count on those marks staying " gone"! The ink is still present. A few hours in a cold car trunk while transporting, or displayed in a winter " sun room", and those black or purple marks are right back! I now use the blue ink water erase or purple ink " air erase" . I find l tsp. of baking soda mixed with l c tepid water in a spray bottle do a great job at getting rid of the blue water erase with no bleed.