ok wait i am a bit confused, actually. 52 for me is great all around, except the waist band is too big (by like, an inch or more). otherwise i dig how they fit in the hips, thigh, knee, etc.
i wouldn't want the casual ones any bigger in any of those areas. if the casual-er ones fit bigger in all those areas, but are just tighter in the waistband, as long as there is room to let the waistband out in case they're too tight, sounds like maybe 50 is what i should get.... ?