I just finished a table runner using 505 spray and big stitch quilting. I had no issue with the needle gumming or the layers separating. I am not heavy handed with the spray so that might be a factor. I have found that letting the piece sit for a few minutes and/or pressing after the layers are together seems to help. I pressed the runner after. You might try a smaller project first to see how it works for you. Hope this helps a bit.