If you go to this portfolio http://www.dmwfotos.com/galleries/headshots/
on my site the first 6 headshots were made with a 42" round reflector for a background. What appears to be wrinkles are actually "scuff" marks on the semi-metalic fabric. The last four were made in a different session with a Fotodiox 5x7 white background (the kind with a metal springy frame similar to the Westcott or Lastolites mentioned.)
The background is about 24" behind the subjects. The shots were taken at about F11 with a 24-105 at 105. No wrinkles and the background with stand is less than $100. They also have the mottled look backgrounds if anyone is interested.
