These technically work, but you might as well just go a bit higher and buy Yanktz.  These elastic shoelaces come with raggedy ends (just cut off with scissors, looks like) instead of shoelace caps - this is a problem when you have to feed the laces into the little black holder.  Personally, I bought these because they have the turquoise color that Yanktz doesn't (why, Yanktz, why??), so I guess it works well enough.