In short, yes, monokote has changed ... and for the worse. They went to an environmentaly safe formula years ago. That ruined their quality and characteristics. Also, monokote now streches further length-wise as opposed to width-wise of the roll. This becomes noticable if you cover your ribbed wing in different directions (90 degrees) from each other. If you cover your wing length-wise of the roll, the concaves between the ribs will be more predominent (this is bad) than if you used the monokote in a width-wise direction.