you can use any fabric you like. even change colors. its up to you. there is no cross stitch police. they have a handy fabric calculator here that's a BIG help.

Thanks for the reply. Sometimes Lavender and Lace charted the face of the angel in a smaller stitch. (i.e. "over 1" whereas the rest of the chart was "over 2") I couldn't see how to do that on Aida. So, your reply is good news!!!