Quote - The red one looks like plastic. But the 2nd one looks a bit like taffeta because of the near iridescence (just needs a little bump) and the third is getting a lot more like satin. (specifically like charmeuse). Looking good!

Check out these Bing images of charmeuse. You might need a little bump and more reflection (not more specular but added reflection) - 

http://www.bing.com/images/search?q=Charmeuse

Thanks for the feedback...I agree about the red. I was think moire taffeta with the second. I think the third is closest but it still needs more work. I'm currently working on adjusting the reflection strength while using a skydome as at the minute it is reflecting way too much of the blue and turning it very green.

Also still playing with a couple of the other sliders on the reflect and refract brick.