I have always used them and only have problems with the orange and sometimes yellow ones. It all depends on the fabric, of course it is something ya may wanna quilt right away. I think that is what my problem was with those 2 colors, I marked an entire top only to have to stash it for a prompt move and forgot about it for quite some time! Most of the yellow has come out over the years but the orange is still there. But, I still use them, cheap alternative and normally no problems.