I have used the Saral white transfer paper as well, it reminds me a little of the carbon idea we used to use in dressmaking with your little wheel to trace the lines. I found it satisfactory for the wallhanging I did, but I don't think it would be my choice for a whole quilt.
I haven't checked out a silver sharpie yet here....guess I should have done that before I "recommended" his method, huh? Oh well.... even if I can't get it here in Canada...it may be readily available in the US