Personally, I think that either can be very effective if done properly. Pulling off the scare is up to the actor, and, even with the greatest prosthetic or mask, if the person donning it isn't pulling their weight, it really makes no difference how spectacular they look. Another big part of it is lighting, or lack of; under bright lights, nothing will come off as creepy as under low lighting. Just my two cents...
Wide variety of products, including clothing (from child to adult-sized), jewelry, wall clings, dog items, and much more. Many perfectly-suited for Halloween.