I'm finally happy with the front holders. I added material to the bottom of the "ledge" that the top sits on and more material to the bends so they are stiffer but still shouldn't mar a painted hood when it's riding in place. There is a few mm added to the back where they bolt to the trunk for extra strength.
These are made from the same material that the rears are made from so they will be durable and flexible. Production starts this week and I should be shipping (if anyone wants them) Friday.