Bill,....I've used them, If anyone haz had reactions later in their paint, I would think it was poor prep of the area, if you don't leach out the tinning butter (acid) it could come back to bite you later, esp if you open up the solder with a file/sandpaper, and leave the surface coarse, acetone/laquer thinner the lead joint,...even factory lead joints if they've been ground/sanded apon

Mike