I use the Frixion pens and because of all the controversy I ran my own tests on them. I found that the lines mostly disappear with ironing and return when placed in the freezer. I then washed and dried the fabrics and put them back in the freezer. The ink was completely gone after washing. Not an issue for me because I wash everything after it's finished.

I love the Frixion pens. I haven't had any problems, but use caution as stated. You can find them at the office supply stores very reasonable. I just picked up 2 pkts of three at Staples for $7. Not a bad deal to keep them around. I also like the Clover marking chalk wheel. It comes in several colors and you just brush off.

I have used the Frixion pen in black to mark my embrodery lines for my quilt labels and quilting lines on one of them. The fabric was all white and the iron took out all the lines. I love the fine line they make. I am told that they might return at 14 degrees but not many of us will be putting our quilts in the freezer nor will they be going to places where they will be exposed to that temp. Since I wash all my quilts before they leave then I shouldn't have to worry about that anyway, right RoseL?

I love the FriXion pens & haven't had a problem with markings returning after I iron them. :-)

I use the frixion pens as well and love them with no problems. Even a blow dryer will errase it. Or throw the item in the dryer, marks are gone.

I've used the Pilot FriXion ball pen in red and blue and never had any problem with either of them. A gal in a local quilt shop told me to buy them at the stationery store, they are a lot cheaper there than in the quilt shops.

I have used them and have them disappear even before I am ready for the to do so. Not sure if they should do this or whether I just take too long to stitch them. lol.

Frixion pens are my choice-I love them! Just press and the markings disappear!

I use the blue disapearing ink pens but only do a small section at a time since the lines fad out fast.
Never have had a problem using them.

The mark be gone pens are my choice for light colored fabrics - sometimes when they dry they will come back. To avoid this problem mix a tsp of baking soda in a pint of distilled water. Learned this trick from a chemist, something to do with the mineral content of the water. She was also a quilter.
As for dark fabrics, I go for my tailors wax piece. Always test on a edge or something when marking a customer quilt. If there is any poly content in the fabric there will be a faint evidence of the mark. Remove this with your iron. If you don't have it, get a few friends to go in with you on a box of the stuff. I get it from Atlanta Thread and just a piece or two lasts me for years. Its the giant one. Don't buy the colors - don't come out. The company seems to have merged with another and the wax is on sale. I teach my new customers about using the wax and give them a sample piece when they first start coming to me for quilting.