I ordered these somewhat by mistake -- I had intended to buy the larger size (50 mm), but I guess my American brain couldn't process the difference with the tricky metric system and I ordered these instead. I really like them. They are beautifully designed and the grid lines are noticeable but also faint and unobtrusive.

That all said, I have to agree with another reviewer (of a different version) who said these do not accept ink very willingly. Indeed, they seem almost to be the opposite of Rite in the Rain products, which are designed to survive the toughest elements. These sticky notes seem to repel any ink you throw at them. I don't just mean fountain pen ink, but uni Signo, Jetstreams, microns, you name it and it probably won't dry completely, even after a few hours. It's kind of a feat of engineering in a really, really bad way.

What can I say though, I still really like these and hope to find a way to make them work for me.

These do the job to let me scribble notes in library books without hurting them.

It's a new technology! It's great to put on the textbooks with my note. I can still see through the textbooks.

I really like these sticky notes. It gives me the ability to see what's underneath what I'm reading. The only downside is the dry time is really long and some pens like the paper mate flair don't work well. I've also tried the uni ball signo and it took awhile to dry.

Too expensive. The product is nice, but you don’t get very many sheets.

Don't like these stickies. Too difficult to write on.

I use this to temporarily add appts in my Hobonichi. Once the appointment happens, I write it in the notebook. I love the size and the grid lines. I write on the sticky notes using mechanical pencil.

I got this one by mistake thinking they were the bigger size, but I absolutely love them. I am ordering more in the future and ill try the other available sizes