when i trim around the outside of my paper pieced blocks i do use a rotory cutter- but i have 2 - one with an old blade- which i use for paper- fusables ect- one with a nice sharp blade for cutting fabrics- when the fabric blade becomes dull starts skipping i put it in an old case marked old-
then when the old blade cutter is really not working well on paper ect i can change it out to one in the 'old blade case'