It would be easier to say what machines are junk.
Plastic = JUNK
Stamped metal = JUNK
Some vintage machines ARE better than others. If you can come up with a real nice high end European - some of those are very nice vinatage machines. I'm partial to Elna - the old blue ones are nice. Some people are partial to vintage Pfaff or Viking or Bernina... I think it also depends on how much money you have to burn. If you buy any vintage machine that has been reconditioned, expect to pay a bit more depends too on who reconditioned it. I think the main thing is that you have fun with it. I guess since I learned on a FW I don't see it as any big deal.
Some how I have not been able to load pictures any more - I don't know what changed. I had hoped to load some pics... bummer...