Interactive Clothes Performance

Hello.

I'm trying to make a virtual dressing room. Something similar to this: http://www.youtube.com/watch?v=jDpiIbxDbvs

But I would want the clothes to act more real, so my guess was to use interactive clothes. What is the max number of vertices/triangles before I start to slow down on perfomance? What are good practices to achieve what I'm looking for. Or are there any better alternatives?

Thank you.