That is a very good point about the 1 lb bottles. They really aren't meant to be refilled. Some people do it and haven't had any issues but it's only ok until you have a problem, then it's a serious problem. I have never refilled one because I'd rather not be next to a 1 lb Propane grenade when the fuse goes off. That would be messy and probably my last day on earth. Not worth the risk to me.