I use 30 by default, unless something necessitates 25. I’ve never heard of weight influencing flap setting, unless you’re looking at a climb limit, but that’s more of a single engine factor. Flap 25 does give you SLIGHTLY better tail clearance though. If your landing technique is sound, this shouldn’t be an issue though. I’d rather go with 30 and have an approach speed 7-8kt slower.