Fleece doesn't fray like flannel so the look will be entirely different from a tradtional rag quilt made with woven fabric like flannel. Rather than the frayed edge you will get more of a fringe look. Here is a link to a blog that has a good picture of what it will look like and it will retain this look through washing. I don't think it would look nice if you mixed flannel and fleece because the flannel will fray and the fleece won't. Additionally I have no idea how deep the cuts are in the accuquilt die. You may have to make deeper cuts working with fleece.
http://www.instructables.com/id/No-S...ece-Blanket-1/