They're great pens!
However, be aware that while the hot iron removes the ink ... sometimes there is a bleached line on the fabric (both dark and light fabrics) as a result. TEST it as you would use it ... with the identical fabrics and treatments, and make your decisions.
I love the ones I have, and most of the time, I use them on the back side to mark fabric, so the bleaching isn't really a concern for me.
And yes, they are the same pens as you can buy at Staples. I bought a pack with several different colours, for a lot less than the individual pricing would have been at the LQS.