I uses these on occasion so if they are sitting in the cabinet over time they still don't lose their stickiness! I like that they actually stick to the surface of most things.
I bought these for my classroom. These Staples 3x3 Recycled Yellow Notes are ok. They do the job for a short term. The ones I got didn't want to stick to everything I needed them to. Maybe it was the humidity in my classroom? Not sure but the brand name ones did a fine job. That said I'll probably buy them again for classroom activities that are shorter in duration but probably not for any notes I need to stay in place for more than a day. Hope someone else has better luck with them than I did.