Lisa,
I just bought my first spool. I was having issues counting Baroque which is the biggest chart I've ever attempted with a huge border, so I'm going to try this. I may try to use it on my HAED Mermaid too. Hopefully this will help me with those 564 stitch borders. I just can't count, and it seems silly to buy 60 pins to mark my groupings of 10 off. I'll let you know as soon as it arrives and I give it a chance.

WIP's:  Chatelaine Designs (KnotGarden, Fairy Flower Garden, Rahjasthan Lotus Garden, Queen's Farmhouse), Shepherds Bush (Sophie's Roses), TGOSM (Mermaid Jewell Case), Miribilias (StarGazer, Sabrina), Carriage House (Christmas at Hawk Run Hollow), HAED (Mermaid)
Waiting in the wings:  Baroque, Venice Mandala, Sophie's Stocking