i use tons of flannels and fleece on occassion- both are good in quilting- make soft/fluffy/cozy quilts- i also mix textiles often- meaning the same quilt may contain regular flat cottons, flannels, homespuns, fleece, corduroy,wool...you get the point. as long as i can wash/dry it all together i will use it all together- if it fits the project i am doing