Pulled this picture off a slingshot Facebook page. He was in a crash and received a serious laceration from his head hitting the slingshade top.
You can't control other people's driving so be defensive.
I'll agree, I've noticed nearly every inch of my Slingshade is either a rough cut or a sharp edge. I've used a file to soften a few of the edges already and I intend to do the entire thing, soon. The whole thing is made of fiberglass and files down pretty easily, but left unchecked, it's like being surrounded by a bunch of knives.