Review (3/5): The black ones work well. The others? Not so much.
Unless you like digging your scalp and pulling through tangled hair, then avoid the metallic ones. They have rounded ends that I think are supposed to protect your scalp and keep it in place, but instead, they cause it to get tangled. The black ones aren’t rounded; they aren’t sharp either and no tangles. They are an entirely different, more appropriate medal and a good design too. I’d skip the “multicolor” ones and go straight for a purchase of the black ones. I’m blonde, but they screw in right so it’s not a problem. And it’s much better than having a matching color either sticking out or sticking to head. Ouch!