I also use Sharon Schambers' method of basting. a) it's cheap because i can use the extra embroidery floss i have left over from my cross stitch days and b) I don't get overspray - don't have anywhere to spray it anyway.
I can't imagine trying to spray a large quilt anyway and keeping it straight. The same thing for the fusible batting - I only have a regular size ironing board, so ironing that all to get it down well enough isn't happening w/ my set up. Reality is that I can baste it quicker than I can mess w/ that other stuff anyway.