I use those clips and haven't had any problems.
Another thing that I use is used larger sewing machine needles or used long arm needles. If I want to hang a small quilt on a wall (lap sized or smaller) and I don't want to use a quilt hanger I position the quilt where I want it to be and use my old needles as anchors in the quilt. I push the used needles through the quilt at the corners and tap the needles into the wall. If the quilt needs extra support in the middle, I just use more needles. The quilt hangs straight because it is supported. I do take the quilts down every so often and re-hang them. When the machine needles are removed from the wall, there is hardly a mark in the wall and I've never had a quilt damaged. But, I've not used this on a larger sized quilt.