I just finished my Amy Butler Birdie Sling. I absolutely love this bag. It is so big. It's perfect for carrying my school stuff around campus. This pattern is really easy. It just requires a lot of cutting pieces out because all the pieces are interfaced. In Canada we don't have easy access (well I don't at least) to Pellon products which are what the pattern suggested. I used some fusible fleece for the lining pieces and a lightweight woven fusible for the exterior pieces. I didn't want something too heavy for the exterior pieces so I went with the lightweight. Great pattern!