A friend of mine just completed her 1st quilt top and she had pressed all her seams open. The only suggestion I could make to her at the time was to press them thoroughly as they had not been. Either way you press them, I just suggest you make sure they are pressed as flat as possible as they could get pushed to the side when you're sewing the rows together and/or when it comes time to put the layers together for quilting. I went back to press my friend's quilt top and its laying much better now. Hope she likes how I quilt it for her. She did a very good job I feel for being her very 1st quilt.