For me, SS is fine (probably easier)for 35mm and I only use plastic (Patterson) for 120.(posted 8807 days ago)I've never loaded 120 on a SS reel without getting kink marks, and have only seen this rarely with plastic reels.
BUT, a lot has to do with the thickness of the film base. Verichrome Pan, for example, is the thinnest I've found. TMax 400, is at least 30% thicker. Kodak specs confirm this.