I haven't used the Madeira brand, but I use Superior's Vanish water soluble thread in the longarm. I did notice that the last time I used it I had more breakage than usual, and I thought it might be because the weather was warmer and more humid. I slowed down and got my basting done. Superior also sells a heavier duty water soluble, and I think I may try that for the longarm next time. I wonder if it would help to put the thread (in a plastic bag) into the refrigerator for a little while before using? I don't know if that would keep it from absorbing moisture from the air so quickly or not. It is aggravating when it breaks, but I seldom had that problem in the cooler weather.