Sorry for the late reply, was at work. I actually bought some during my shift today. They're very hit or miss.

They write pretty smoothly and once on paper, it does look similar to a pencil. Probably fine for jotting notes but doesn't seem to be a replacement for the pencil as a sketch tool.

It also seems the output changes depending on what angle you hold the "pen" at. Felt awkward to me but a co-worker loved it. Probably not worth the $4.99 OfficeMax sells them for at the moment but if you can find them cheaper, worth a shot.