Some people choose not to put in batting because glassware tends to be unstable on it. I don't own any stemware at all, so not an issue for me (coffee, teacups, mugs - all go on tablerunners just fine without tipping). Since I don't know how the table runner would be used, I would use Warm and Natural or that Thermo stuff for batting. That way, if they set a hot casserole on it thinking it works just like a hot pad, their table doesn't suffer. I know some people have used felted wool as a batting, but wool continues to shrink every time it is washed and dried and can result in funky shifting within the project.