I was honestly very impressed from the first time I used them. I kept messing up on purpose. I used the pens all at once so see if one would not erase properly, they did. I let the ink set for a few hours, then went back to erase, still worked. I loved the highlighters. Both the pens and highlighters were smooth, no need to go over twice or more to make it noticeable. I let my kids (10 yr old girl and 17 yr old boy) use them. My daughter begged me for some for herself, my son just said they were cool. For a teenage boy, that means they are great.