Raw edge applique is probably one of the best uses for the scan n cut. I bought one last year, and have used it mostly on paper, only a little on fabric. When using it to cut fabric that does not have a fusible adhered to it you add a "support mat" to your cutting mat to stiffen it. The support mat is permanent, so you will have to dedicate that mat to that purpose. I have not yet cut appliques, but my understanding is that with the fusible adhered the support mat is not necessary.
Be prepared to experiment with the cutting blade settings (length and pressure) before using your best fabric. Also, be aware that the cutting mats are a consumable - they eventually lose their stickiness, and can develop grooves from repeated cuttings. I use baby wipes to clean the mat, then let it sit and dry to revive the stickiness. Try not to cut the same shape repeatedly in the same spot to prolong the mat's life.
Good luck!