Jones,
all those areas hold elk, 631 is the smallest of the areas. I have not hunted in 631 or 632. I have hunted 621 although most of my experience has been on the south side of the river. 621 has a closed area where hunting is not allowed. this is by slippery ann, and when the pressure starts, elk congregate in that area, in particular during the bow season. I think you could tag a good bull in any of the areas though.