I own a down Exped Wallcreeper (caught an old model on clearance and it was nearly as cheap as making my own would have been). It works in all three configurations and also as long vest with a hood thanks to the zippered armholes. In order to use your creation as a flat quilt, you are going to have to have the full length of you body plus enough to keep your feet covered as the quilt goes over your body -- this is ample for the construction of a foot box when using this design.