The advantage of using a power sander is if there are any scratches that scored the metal, sanding it can smooth those out where stripping it is still going to leave them there. Just wear protection whatever you do - if you sand, the paint might have lead in it and when you turn it into dust that can be really bad. If you strip, usually the chemicals are not good for your skin, and can have toxic fumes (and again if there is lead in the paint it can harm you).