I picked this up as an auction item, as I was curious to see how it compared with other roughing
options. It’s not bad, but I found it a little finicky. If you follow the instructions (though I
did need a heavier application to both cards), this performs pretty well. But it does seem to work
more by adhesion than friction, which means the cards hold pretty well until separated but not as
well if you’re trying to re-adhere the cards on the fly. I’m not sure I’d buy this over other
products on the market, but it’s okay for the price and a block will last you a while.