I really need help. I saw a singer 15-91 today that was made in 1952. It is in a refinished cabinet with drawers and has a bench seat with it. It has some attachments, one might be a button hole attachment, and the instruction book. Do I need it? Probably not, but should I get it? I have a Featherweight and a 99 that I have acquired since May. Any good reasons why I should get it. I haven't found any info on the net about them that is helpful at this time. If I am to get it, I need some concrete ideas of why to get it to pose to my husband about it. I know the attachments will fit the other two machines, but is this enough to warrant getting it? HELP!!