Some say that medals and crosses are nothing but material items and offer no real protection. In my opinion, if it comforts you or you have belief or faith in it, then by all means wear it.
I myself will always wear my crystals, or cross, or my protection medals. I always carry one of them with me; it gives me a sense of peace and protection. It is all in what you believe in and if it works for you, go with it.