I have the Pounce system and do not like it. Marked an entire quilt only to have the powder come off before I could get it set up on my long arm frame. Would not recommend spending the money.
Took a class from Cindy Needham. She told us to test any marker on an inconspicuous part of the quilt and then try to wash it off. This saves you the time and aggravation of doing something wrong.
I have used a variety of marking pens and pencils and always seem to need a color I don't have.
Chris