Originally Posted by old and new
Vintage is cool,that ought not to be your biggest concern.Vintage excludes bike made after '82,that's elliminating a big chunk of what's out there.A bike from after the early '80s had a better range of components; better sizing(metric),many more choices spec'd with 700 wheels and just plain newer.I feel all the concerns of all that makes a vintage may not matter as much.
Think "quality used" rather than vintage, although "quality used" may include vintage.
After 94 though many more were aluminum so the choices may tail off from then on.
Look for steel, rather than aluminum. It lasts longer, won't fail catastrophically the way aluminum does, and won't be a harsh ride, the way aluminum is.
$400 which you stated post original post does provide lots of choices,a very realistic price point,I'm sure my esteemed colleagues would agree on THAT.
Yep!