When I first got these markers, I loved them. I don't use them on a really regular basis, but I use at least one every day to jot a couple of notes down on a black marker board I have at work. I keep them stored upside down, like you're supposed to. When I use one, it works great at first, and then it gets lighter and lighter as I write. If I put the marker down for a while and then pick it back up, same thing happens. It works great for a while, and then the color starts to fade as I write. They work for what I use them for, but if you plan on doing a lot of writing with them at one time, I don't know that they'd be the best buy for you.