Review on 🖌️ Brighten Up Your Art with FANTASTIC ChalkTastic's Reversible White Chalk Marker & Pens - 4 Pack (6mm Fine & Chisel Tip) - Perfect for Bistro Menu Boards, Glass Windows, and Kids' Art - Erasable Paint Marker in Bold White Color by Michelle Langley

Great. It's worth it. Used for signage at my country wedding tonight (see image for example) which was done with chalkboard paint. Unfortunately it rained all day during the wedding. Direct exposure to light rain caused the run to take about 15 minutes. The signs, which were at the venue, were exposed to humid air but not direct rain and did not bleed or smudge at all. There were four markers in the pack but I only used two of them for about 10 characters including text and embellishments. . The nib dulled a little after about 5 or 6 marks (I also unknowingly use quite a bit of force when writing, if you can avoid it I expect the nib to last much longer).